Open Collections

UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

Evidence for adaptive relationships between body morphology, body size and swimming performance in British… Taylor, Eric Burke 1984

Your browser doesn't seem to have a PDF viewer, please download the PDF to view this item.

Item Metadata

Download

Media
831-UBC_1984_A6_7 T39.pdf [ 5.29MB ]
Metadata
JSON: 831-1.0096165.json
JSON-LD: 831-1.0096165-ld.json
RDF/XML (Pretty): 831-1.0096165-rdf.xml
RDF/JSON: 831-1.0096165-rdf.json
Turtle: 831-1.0096165-turtle.txt
N-Triples: 831-1.0096165-rdf-ntriples.txt
Original Record: 831-1.0096165-source.json
Full Text
831-1.0096165-fulltext.txt
Citation
831-1.0096165.ris

Full Text

EVIDENCE FOR ADAPTIVE RELATIONSHIPS BETWEEN BODY MORPHOLOGY, BODY SIZE AND SWIMMING PERFORMANCE IN BRITISH COLUMBIA POPULATIONS OF JUVENILE COHO SALMON,ONCORHYNCHUS KISUTCH by ERIC BURKE TAYLOR B . S c . ( H o n . ) , U n i v e r s i t y o f B r i t i s h C o l u m b i a , 1981 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE i n THE FACULTY OF GRADUATE STUDIES (Dep a r t m e n t o f Z o o l o g y ) We a c c e p t t h i s t h e s i s a s c o n f o r m i n g t o t h e r e q u i r e d s t a n d a r d THE UNIVERSITY OF? BRITISH COLUMBIA J u l y 1984 © E r i c B u r k e T a y l o r , 1984 In presenting t h i s thesis i n p a r t i a l f u l f i l m e n t of the requirements for an advanced degree at the University of B r i t i s h Columbia, I agree that the Library s h a l l make i t f r e e l y available for reference and study. I further agree that permission for extensive copying of t h i s thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. I t i s understood that copying or publication of t h i s thesis for f i n a n c i a l gain s h a l l not be allowed without my written permission. Department of The University of B r i t i s h Columbia 1956 Main Mall Vancouver, Canada V6T 1Y3 DE-6 (3/81) i i ABSTRACT M o r p h o l o g i c a l c o m p a r i s o n of t e n p o p u l a t i o n s o f j u v e n i l e c o ho salmon, O n c o r h y n c h u s k i s u t c h , from s t r e a m s t r i b u t a r y t o t h e F r a s e r R i v e r u p s t r e a m of H e l l ' s G a t e and s t r e a m s i n t h e l o w e r F r a s e r V a l l e y and S t r a i t of G e o r g i a r e g i o n s u g g e s t e d t h a t c o a s t a l j u v e n i l e s were more r o b u s t ( d e e p e r b o d i e s and c a u d a l p e d u n c l e s , s h o r t e r heads and l a r g e r median f i n s ) t h a n i n t e r i o r j u v e n i l e s . D i s c r i m i n a n t f u n c t i o n a n a l y s i s i n d i c a t e d t h a t j u v e n i l e coho c o u l d be i d e n t i f i e d a s t o r i v e r of o r i g i n w i t h 71 p e r c e n t a c c u r a c y ; j u v e n i l e s f r o m c o a s t a l s t r e a m s were l e s s s u c c e s s f u l l y c l a s s i f i e d as t o s t r e a m o f o r i g i n (48-64 p e r c e n t ) t h a n j u v e n i l e s f r o m i n t e r i o r s t r e a m s (83-93 p e r c e n t ) ; however, j u v e n i l e s c o u l d be s u c c e s s f u l l y i d e n t i f i e d as of e i t h e r c o a s t a l or i n t e r i o r i n o r i g i n w i t h 93 p e r c e n t a c c u r a c y . F e a t u r e s o f body r o b u s t n e s s were i m p o r t a n t i n d i s c r i m i n a t i n g between c o a s t a l and i n t e r i o r i n d i v i d u a l s . T h r e e p o p u l a t i o n s were s t u d i e d i n d e t a i l : C o l d w a t e r R i v e r ( i n t e r i o r ) , Wade C r e e k ( l o w e r F r a s e r R i v e r V a l l e y ) and M o r r i s o n C r e e k ( e a s t c o a s t o f V a n c o u v e r I s l a n d ) . In t h e s e p o p u l a t i o n s t h e c o a s t a l - i n t e r i o r m o r p h o l o g i c a l d i f f e r e n c e s were c o n s i s t e n t o v e r s u c c e s s i v e y e a r s , and i n l a b o r a t o r y r e a r e d i n d i v i d u a l s . T h e s e e x p e r i m e n t s s u g g e s t t h a t t h e m o r p h o l o g i c a l d i f f e r e n c e s between c o a s t a l and i n t e r i o r f i s h a r e , a t l e a s t , i n p a r t i n h e r i t e d . In a d d i t i o n , a d u l t coho from t h e C o l d w a t e r R i v e r and M o r r i s o n C r e e k , e x h i b i t e d m o r p h o l o g i c a l d i f f e r e n c e s s i m i l a r t o t h e j u v e n i l e s . B u r s t swimming t e s t s , u s i n g b o t h w i l d and l a b o r a t o r y r e a r e d i n d i v i d u a l s f r o m t h e t h r e e s t u d y s t r e a m s , i n d i c a t e d t h a t i n t h e f i r s t few h u n d r e d t h s o f a s e c o n d of a " f a s t - s t a r t " t h e r o b u s t -b o d i e d c o a s t a l j u v e n i l e s a t t a i n g r e a t e r b u r s t v e l o c i t i e s t h a n s i m i l a r s i z e d i n t e r i o r j u v e n i l e s . In a d d i t i o n , newly emerged f r y f r o m M o r r i s o n C r e e k a t t a i n e d g r e a t e r b u r s t v e l o c i t i e s , and had g r e a t e r s u r v i v a l from p r e d a t i o n , t h a n Wade C r e e k f r y . B o t h Wade C r e e k and M o r r i s o n C r e e k a r e c o a s t a l p o p u l a t i o n s but M o r r i s o n C r e e k f r y a r e l a r g e r a t emergence t h a n Wade C r e e k f r y . In f r i c t i o n a l d r a g d e t e r m i n a t i o n s and s t a m i n a swimming e x p e r i m e n t s , t h e f u s i f o r m i n t e r i o r ( C o l d w a t e r R i v e r ) j u v e n i l e s had b o t h l o w e r d r a g c o e f f i c i e n t s and g r e a t e r s t a m i n a t h a n t h e r o b u s t - b o d i e d i n d i v i d u a l s f r o m Wade and M o r r i s o n c r e e k s . T h e s e o b s e r v a t i o n s s u g g e s t t h a t body form i n j u v e n i l e coho salmon i s a d a p t i v e . The f u s i f o r m body shape o f i n t e r i o r coho may be t h e r e s u l t of s e l e c t i o n f o r i n c r e a s e d s u s t a i n e d swimming p e r f o r m a n c e due t o t h e l o n g and d i f f i c u l t f r e s h w a t e r m i g r a t i o n s t h e s e s t o c k s must p e r f o r m . In c o n t r a s t , s i n c e c o a s t a l p o p u l a t i o n s make r e l a t i v e l y s h o r t f r e s h w a t e r m i g r a t i o n s , body form may be s u b j e c t t o l e s s i n t e n s e s e l e c t i o n . Body form i n c o a s t a l c o h o , however, may be s u b j e c t t o s e l e c t i o n f o r f e a t u r e s t h a t r e d u c e s u s c e p t i b i l i t y t o p r e d a t i o n , i . e. deep, r o b u s t b o d i e s and l a r g e f r y a t emergence. TABLE OF CONTENTS ABSTRACT i i L I S T OF TABLES v i L I S T OF FIGURES i x ACKNOWLEDGEMENTS x i I n t r o d u c t i o n 1 P a r t 1: M o r p h o m e t r i e s 6 M a t e r i a l s and Methods 6 C o l l e c t i o n of S p e c i m e n s 6 B r e e d i n g e x p e r i m e n t s 11 R e a r i n g and M a i n t e n a n c e of W i l d and L a b o r a t o r y P o p u l a t i o n s 13 S t a t i s t i c a l methods 14 R e s u l t s 16 M o r p h o m e t r i e s o f J u v e n i l e s f r o m W i l d P o p u l a t i o n s 16 M o r p h o m e t r i e s o f L a b o r a t o r y R e a r e d P o p u l a t i o n s 29 M o r p h o l o g i c a l T r e n d s and Swimming P e r f o r m a n c e 37 A d u l t M o r p h o m e t r i e s 40 P a r t 2: Swimming E x p e r i m e n t s 41 G e n e r a l methods 41 I n t e r p o p u l a t i o n B u r s t Swimming T e s t s 42 Emergence S i z e - B u r s t P e r f o r m a n c e E x p e r i m e n t 47 P r e d a t i o n T e s t s 48 S t a m i n a Swimming T e s t s 49 S t a t i s t i c a l Methods ...51 V Dead Dr a g D e t e r m i n a t i o n s 53 R e s u l t s 57 B u r s t Swimming E x p e r i m e n t s 57 P o p u l a t i o n B u r s t Swimming 57 S i z e - a t - E m e r g e n c e 63 P r e d a t i o n E x p e r i m e n t s 68 S t a m i n a Swimming E x p e r i m e n t s 68 Dead Dr a g D e t e r m i n a t i o n s 73 D i s c u s s i o n 78 M o r p h o l o g i c a l V a r i a t i o n i n Coho Salmon 78 M o r p h o l o g i c a l V a r i a t i o n and A d a p t a t i o n 81 P r e d a t i o n and A d a p t a t i o n 91 L i t e r a t u r e C i t e d 98 A p p e n d i x 111 v i L I S T OF TABLES T a b l e 1. B i o p h y s i c a l d e s c r i p t i o n of t h e n a t a l s t r e a m s of t h e t h r e e s t u d y p o p u l a t i o n s ....10 T a b l e 2. M o r p h o m e t r i c measurements u s e d i n t h e s t u d y . ......12 T a b l e 3. A d j u s t e d g e o m e t r i c means of measurements and r e s u l t s o f ANOVA c o m p a r i n g p o o l e d c o a s t a l and i n t e r i o r p o p u l a t i o n s 21 T a b l e 4. C l a s s i f i c a t i o n r e s u l t s u s i n g j u v e n i l e coho s p e c i m e n s from n o r t h c o a s t a l B.C., A l a s k a and t h e upper C o l u m b i a R i v e r s y s t e m 28 T a b l e 5. Spearman rank c o r r e l a t i o n a n a l y s i s of body measurements and d i s t a n c e t o t h e s e a of spawning s t r e a m s 38 T a b l e 6. Swimming p e r f o r m a n c e rank p r e d i c t i o n s b a s e d upon m o r p h o l o g i c a l rank f o r t h e t h r e e s t u d y s t r e a m s 39 T a b l e 7. R e s u l t s o f m o r p h o m e t r i c a n a l y s i s f o r a d u l t s from t h e C o l d w a t e r R i v e r and M o r r i s o n C r e e k 41 T a b l e 8. R e g r e s s i o n a n a l y s i s o f mean v e l o c i t y (cm/s) p e r b u r s t s e quence on s t a n d a r d l e n g t h (mm) f o r w i l d and l a b o r a t o r y r e a r e d j u v e n i l e c oho from t h e t h r e e s t u d y p o p u l a t i o n s 58 T a b l e 9. R e g r e s s i o n a n a l y s i s of maximum v e l o c i t y p e r b u r s t s e q u e n c e ( c m / s) on s t a n d a r d l e n g t h (mm) f o r w i l d and l a b o r a t o r y r e a r e d j u v e n i l e coho from t h e t h r e e s t u d y p o p u l a t i o n s 59 v i i T a b l e 10. R e s u l t s of c o v a r i a n c e a n a l y s i s on mean b u r s t v e l o c i t y on s t a n d a r d l e n g t h and maximum b u r s t v e l o c i t y on s t a n d a r d l e n g t h f o r w i l d and l a b o r a t o r y r e a r e d j u v e n i l e coho from t h e t h r e e s t u d y p o p u l a t i o n s 61 T a b l e 11. A d j u s t e d mean and maximum v e l o c i t i e s a t t a i n e d d u r i n g b u r s t a c t i v i t y f o r w i l d and l a b o r a t o r y r e a r e d j u v e n i l e s from t h e t h r e e s t u d y p o p u l a t i o n s 62 T a b l e 12. Female s t a n d a r d l e n g t h , egg volume and emerged f r y s t a n d a r d l e n g t h f o r Wade and M o r r i s o n C r e e k coho p o p u l a t i o n s 64 T a b l e 13. B u r s t swimming p e r f o r m a n c e summary o v e r 0.05 s e c o n d s f o r emerged coho f r y from Wade and M o r r i s o n C r e e k s 67 T a b l e 14. S u r v i v a l f r o m p r e d a t i o n by coho f i n g e r l i n g s , and s i g n i f i c a n c e o f d i f f e r e n c e s , o f newly-emerged f r y from Wade and M o r r i s o n C r e e k s 69 T a b l e 15. C o m p a r a t i v e s t a m i n a swimming p e r f o r m a n c e among w i l d r e a r e d j u v e n i l e c oho from t h e t h r e e s t u d y p o p u l a t i o n s 71 T a b l e 16. C o m p a r a t i v e s t a m i n a swimming p e r f o r m a n c e among l a b o r a t o r y r e a r e d j u v e n i l e coho f r o m t h e t h r e e s t u d y p o p u l a t i o n s 72 T a b l e 17. C o m p a r a t i v e v a l u e s o f d r a g c o e f f i c i e n t s and c a l c u l a t e d f r i c t i o n a l d r a g a t a swimming v e l o c i t y of 30 cm/s f o r c o a s t a l and i n t e r i o r j u v e n i l e c o h o s p e c i m e n s . ..74 T a b l e 18. L i s t o f documented, o r p o t e n t i a l , f i s h and b i r d p r e d a t o r s on j u v e n i l e coho salmon and t h e i r r e l a t i v e d i s t r i b u t i o n s i n B r i t i s h C o l u m b i a . L I S T OF FIGURES F i g u r e 1 . F r a s e r R i v e r System and t h e S t r a i t of G e o r g i a r e g i o n 7 F i g u r e 2. D i s c r i m i n a n t f u n c t i o n a n a l y s i s d e s c r i b i n g m o r p h o l o g i c a l v a r i a t i o n among t e n p o p u l a t i o n s of j u v e n i l e coho salmon 18 F i g u r e 3. P h o t o g r a p h of r e p r e s e n t a t i v e c o a s t a l ( u p p e r -M o r r i s o n C r e e k ) and i n t e r i o r ( l o w e r - C o l d w a t e r R i v e r ) j u v e n i l e coho salmon 22 F i g u r e 4. Two-group d i s c r i m i n a n t f u n c t i o n a n a l y s i s d e s c r i b i n g m o r p h o l o g i c a l v a r i a t i o n between c o a s t a l ( ) and i n t e r i o r ( ) w i l d coho salmon p o p u l a t i o n s 24 F i g u r e 5. D i s c r i m i n a n t f u n c t i o n a n a l y s i s d e s c r i b i n g m o r p h o l o g i c a l v a r i a t i o n among w i l d j u v e n i l e c oho from t h e t h r e e s t u d y p o p u l a t i o n s , 1982 30 F i g u r e 6. D i s c r i m i n a n t f u n c t i o n a n a l y s i s d e s c r i b i n g m o r p h o l o g i c a l v a r i a t i o n among w i l d j u v e n i l e c oho from t h e t h r e e s t u d y p o p u l a t i o n s , 1983 32 F i g u r e 7. D i s c r i m i n a n t f u n c t i o n a n a l y s i s d e s c r i b i n g m o r p h o l o g i c a l v a r i a t i o n among t h e l a b o r a t o r y r e a r e d j u v e n i l e coho salmon from t h e t h r e e s t u d y p o p u l a t i o n s . ..35 F i g u r e 8. P o r t i o n of f a s t - s t a r t r e s p o n s e a n a l y s e d i n b u r s t swimming e x p e r i m e n t s 45 F i g u r e 9. Drop t a n k a p p a r a t u s u s e d i n f r i c t i o n a l d r a g c o e f f i c i e n t e x p e r i m e n t 54 X F i g u r e 10. V e l o c i t y - t i m e r e l a t i o n s h i p s f o r Wade and M o r r i s o n C r e e k emerged f r y 65 F i g u r e 11. F r i c t i o n a l d r a g f o r c e as a f u n c t i o n of v e l o c i t y f o r j u v e n i l e coho 76 x i ACKNOWLEDGMENTS T h i s s t u d y was c o m p l e t e d under t h e major s u p e r v i s i o n of Dr. J.. D. M c P h a i l w i t h whom i t has been a s i n c e r e p l e a s u r e t o be a s s o c i a t e d . I w i s h t o thank him f o r h i s a d v i s e , g u i d a n c e and f i n a n c i a l s u p p o r t p r o v i d e d t h r o u g h o u t t h e s t u d y . Dr . P. A. L a r k i n c o - s u p e r v i s e d t h e s t u d y and p r o v i d e d s u p p o r t and h e l p f u l c r i t i c i s m s on t h e m a n u s c r i p t . D r . R. W. B l a k e p r o v i d e d camera e q u i p m e n t , c o n s t r u c t i v e c r i t i c i s m and s t i m u l u s d u r i n g t h e s t u d y . Two o f my c o l l e a g e s and f r i e n d s d e s e r v e s p e c i a l t h a n k s . P a t r i c k L a v i n a s s i s t e d g r e a t l y i n h e l p i n g me t o a p p r e c i a t e many a s p e c t s o f s t a t i s t i c s and e v o l u t i o n , v i a o u r numerous d i s c u s s i o n s , w h i l e p r o v i d i n g s e v e r a l c o n s t r u c t i v e c r i t i q u e s o f t h e m a n u s c r i p t . A l s o , f o r c o n s i d e r a b l e a s s i s t a n c e b o t h i n t h e l a b o r a t o r y and i n t h e f i e l d I t h a n k G a r y B i r c h . P a t r i c k L a v i n , S t e v e C o x - R o g e r s and N i n i G i b s o n a l s o p r o v i d e d f i e l d a s s i s t a n c e , w h i l e M a r v i n Rosenau was k i n d enough t o r e v i e w an e a r l i e r d r a f t of t h i s t h e s i s . I have a l s o b e n e f i t e d c o n s i d e r a b l y f r o m d i s c u s s i o n s w i t h C h r i s F o o t e and Doug S w a i n . F o r s t i m u l a t i n g my i n i t i a l i n t e r e s t i n t h e b i o l o g y of f i s h e s I thank D r . N. J . W i l i m o v s k y . Dr. Dave Z i t t i n and Susan E r t i s p r o v i d e d p a t i e n t a s s i s t a n c e w i t h c omputer programming f o r w h i c h I am g r a t e f u l . I thank x i i D r . T. Howard of t h e B. C. R e s e a r c h C o u n c i l f o r t h e l o a n of t h e s t a m i n a a p p a r a t u s and Dr. T. P i e t s c h of t h e U n i v e r s i t y o f W a s h i n g t o n f o r p r o v i d i n g a c c e s s t o t h e U o f W c o l l e c t i o n s o f j u v e n i l e coho from t h e C o l u m b i a R i v e r . 1 INTRODUCTION The i d e n t i f i c a t i o n o f g e n e t i c a l l y d i s c r e t e p o p u l a t i o n s as f u n c t i o n a l management u n i t s has l o n g been a t h e o r e t i c a l g o a l f o r f i s h e r i e s managers ( C a r s c a d d e n and L e g g e t t 1975; G r a n t and U t t e r 1980; W i l k e t a l . 1980; M a c l e a n and E v a n s 1981; Todd e t a l . 1981; N i 1982). G i v e n t h e i r t e n d e n c y t o home t o a n a t a l s t r e a m , and form d i s c r e t e l o c a l p o p u l a t i o n s , i t i s not s u r p r i s i n g t h a t t h i s " s t o c k c o n c e p t " (Simon and L a r k i n 1972) has been w i d e l y u s e d i n t h e management of many s p e c i e s o f s a l m o n i d s ( R i c k e r 1972; McDonald 1981; U t t e r 1981; F o u r n i e r e t a l . 1984). I n t r a s p e c i f i c v a r i a t i o n i n s a l m o n i d s r e s u l t s f r o m a c o m b i n a t i o n of g e n e t i c i s o l a t i o n between demes and l o c a l e n v i r o n m e n t a l d i f f e r e n c e s ( R i c k e r 1972). The r e l a t i v e c o n t r i b u t i o n o f e i t h e r g e n e t i c o r e n v i r o n m e n t a l f a c t o r s t o t h e p h e n o t y p e , however, v a r i e s among t r a i t s ( B a r l o w 1961; I h s s e n and T a i t 1974). W i t h i n t h e genus O n c o r h y n c h u s , much of t h e e f f o r t t o d e f i n e g e n e t i c p o p u l a t i o n s has f o c u s s e d on a d u l t p i n k (O. g o r b u s c h a ) , chum (0. k e t a ) and s o c k e y e ( 0 . n e r k a ) salmon (Anas and M u r a i 1969; B i l t o n 1971; Beacham and S t a r r 1982; McGregor 1983; M u l l i g a n e t a_l. 1983). A t t e n t i o n has f o c u s s e d on t h e s e s p e c i e s b e c a u s e o f t h e i r n u m e r i c a l dominance i n t h e c o m m e r c i a l salmon c a t c h . W i t h r e s p e c t t o p o p u l a t i o n s t r u c t u r e t h e coho salmon, 0. k i s u t c h , i s one of t h e l e s s i n t e n s i v e l y s t u d i e d s p e c i e s ( R i c k e r 1972). In many a r e a s , however, ( e . g. t h e B r i t i s h C o l u m b i a s o u t h c o a s t and S t r a i t o f G e o r g i a ) c o h o , a l o n g w i t h 2 c h i n o o k , 0. t s h a w y t s c h a , f orm t h e major component of t h e i n s i d e w a t e r s c o m m e r c i a l t r o l l and s p o r t c a t c h (Argue e t a l . 1983). T h i s s i t u a t i o n c o u p l e d w i t h e x t e n s i v e h a t c h e r y p r o d u c t i o n t h a t has e l e v a t e d t h e i r abundance i n l o c a l i z e d a r e a s t o above h i s t o r i c l e v e l s ( B a r b e r 1983), s u g g e s t s a need f o r an u n d e r s t a n d i n g o f t h e p o p u l a t i o n s t r u c t u r e o f w i l d c o h o . Such i n f o r m a t i o n i s n e c e s s a r y n ot o n l y t o a s s e s s t h e e f f e c t s of a r t i f i c i a l l y p r o d u c e d coho on t h e i n t e g r i t y o f w i l d p o p u l a t i o n s but a l s o t o w i s e l y manage b o t h w i l d and e n h a n c e d p o p u l a t i o n s . The g e n e t i c s t r u c t u r e o f coho p o p u l a t i o n s has been s t u d i e d e l e c t r o p h o r e t i c a l l y but t h e low l e v e l of h e t e r o z y g o s i t y f o u n d i n coho salmon ( U t t e r e t §_1. 1980) s u g g e s t s t h a t g e n e t i c c h a r a c t e r i s t i c s o t h e r t h a n r e f l e c t e d by a l l o z y m e v a r i a b i l i t y may be b e t t e r i n d i c a t o r s of i n t e r p o p u l a t i o n d i f f e r e n t i a t i o n i n t h i s s p e c i e s . M o r p h o l o g i c a l a n a l y s e s have been s u c c e s s f u l l y a p p l i e d t o s t o c k i d e n t i f i c a t i o n p r o b l e m s i n f i s h and some p r o p o r t i o n of i n t e r p o p u l a t i o n d i f f e r e n c e s i n m o r p h o l o g y i s u s u a l l y i n h e r i t e d ( B i l l i n g s l e y 1981; I h s s e n e_t a l . 1981). D e s p i t e t h e l o n g h i s t o r y of m o r p h o l o g i c a l " s t o c k i d e n t i f i c a t i o n " i n v e s t i g a t i o n s i n v a r i o u s f i s h s p e c i e s , and t h e r e l a t i v e e a s e o f d e f i n i n g l o c a l p o p u l a t i o n s t h r o u g h m o r p h o l o g y , l i t t l e i s known o f t h e f u n c t i o n a l s i g n i f i c a n c e o f i n t e r p o p u l a t i o n d i f f e r e n c e s i n m o r p h o l o g y . I d e n t i f i c a t i o n o f i n t e r p o p u l a t i o n d i f f e r e n c e s i n m e r i s t i c s o r m o r p h o m e t r i e s a l o n e does not t e l l us how t h e d i f f e r e n c e s a r o s e . Y e t t h e l e v e l of l o c a l a d a p t a t i o n (Bock 1980) t o s t r e a m s , l a k e s or o c e a n i c r e g i o n s i s p r o b a b l y r e l a t e d 3 t o s u r v i v a l and f i t n e s s of t h e o r g a n i s m s c o m p o s i n g a l o c a l p o p u l a t i o n ( S p a n g l e r e t a l . 1981). Thus, q u e s t i o n s a b o u t t h e a d a p t i v e s i g n i f i c a n c e o f v a r i a t i o n a r e i m p o r t a n t when a t t e m p t i n g t o e v a l u a t e t h e r o l e of s e l e c t i o n i n d e f i n i n g l o c a l p o p u l a t i o n s . The l a c k o f answers t o s u c h q u e s t i o n s c o n c e r n i n g t h e f u n c t i o n a l b a s i s of m o r p h o l o g y r e p r e s e n t s a major s h o r t c o m i n g i n p r e s e n t day f i s h e r i e s knowledge ( I h s s e n e t a l . 1981). S e v e r a l s t u d i e s on A t l a n t i c salmon (Salmo s a l a r ) have s u g g e s t e d t h a t i n t e r p o p u l a t i o n v a r i a t i o n i n m e r i s t i c and m o r p h o m e t r i c t r a i t s may be a d a p t i v e and t h a t some a s p e c t s of body and f i n shape and s i z e may be a s s o c i a t e d w i t h swimming p e r f o r m a n c e ( S c h a f f e r and E l s o n 1975; R i d d e l l and L e g g e t t 1981; R i d d e l l e t a_l. 1981). F u n c t i o n a l r e l a t i o n s h i p s between body m o r p h o l o g y , swimming mode and swimming p e r f o r m a n c e i n f i s h e s have o f t e n been s u g g e s s t e d ( B r e d e r 1926; Kanep 1971; Weihs 1973; B l a k e 1983a) but r a r e l y e v a l u a t e d e x p e r i m e n t a l l y . A few s t u d i e s s u g g e s t t h a t body form and swimming p e r f o r m a n c e a r e f u n c t i o n a l l y r e l a t e d (Weihs 1973; Webb 1977, 1978a; R i d d e l l and L e g g e t t 1981). D e s p i t e t h e d e m o n s t r a t i o n o f s i g n i f i c a n t i n t e r p o p u l a t i o n d i f f e r e n c e s i n s u s t a i n e d swimming p e r f o r m a n c e w i t h i n s a l m o n i d s p e c i e s ( C o l l i n s 1958; Thomas e_t a l . 1964; T s u y u k i and W i l l i s c r o f t 1977), most of t h e s t u d i e s have f o c u s s e d on b u r s t swimming p e r f o r m a n c e and no d i r e c t e v a l u a t i o n o f t h e e f f e c t s of n a t u r a l v a r i a t i o n i n body form on s u s t a i n e d swimming p e r f o r m a n c e have been a t t e m p t e d . 4 The n a t i v e d i s t r i b u t i o n of coho i n t h e n o r t h e a s t e r n P a c i f i c i n c l u d e s b o t h c o a s t a l (west of t h e C o a s t Range) and i n t e r i o r ( e a s t of t h e C o a s t Range) anadromous p o p u l a t i o n s ( F r a s e r e_t a l . 1982; Lee e t a l . 1980). Spawning and s m o l t m i g r a t i o n s may e x t e n d f r om l e s s t h a n 1 km i n s m a l l c o a s t a l s t r e a m s t o o v e r 1,000 km i n t h e upper F r a s e r and C o l u m b i a r i v e r s . T h e s e d i f f e r e n c e s i n d i s t a n c e , and p e r h a p s d i f f i c u l t y , of m i g r a t i o n s u g g e s t t h a t i n t e r i o r and c o a s t a l c oho p o p u l a t i o n s may be under d i f f e r e n t s e l e c t i v e r e g i m e s r e l a t i v e t o s u s t a i n e d swimming p e r f o r m a n c e . Body s i z e i s known t o be an i m p o r t a n t v a r i a b l e a f f e c t i n g b u r s t swimming p e r f o r m a n c e (Webb 1976; Webb and C o r o l l a 1981). F u r t h e r , f r y s i z e a t emergence i s h i g h l y v a r i a b l e between coho p o p u l a t i o n s (Murray 1980), b u t , n e i t h e r t h e r e l a t i o n s h i p between f r y s i z e and b u r s t swimming p e r f o r m a n c e , nor t h e p o t e n t i a l a d a p t i v e s i g n i f i c a n c e of t h i s r e l a t i o n s h i p , have been i n v e s t i g a t e d i n s a l m o n i d s . The p r e s e n t s t u d y i n v e s t i g a t e s t h e r e l a t i o n s h i p between body m o r p h o l o g y and body s i z e and b u r s t and s u s t a i n e d swimming p e r f o r m a n c e i n j u v e n i l e coho s a l m o n . The g o a l s o f t h e r e s e a r c h were t o d e t e r m i n e (1) t h e l e v e l of d i v e r g e n c e o f m o r p h o l o g i c a l f e a t u r e s i m p o r t a n t i n b u r s t and s u s t a i n e d swimming p e r f o r m a n c e between c o a s t a l and i n t e r i o r c o ho salmon p o p u l a t i o n s i n B r i t i s h C o l u m b i a and (2) whether v a r i a t i o n i n t h e s e m o r p h o l o g i c a l f e a t u r e s i s a d a p t i v e . I n v e s t i g a t i o n o f t h e s e c o n d g o a l i n v o l v e d 5 d e t e r m i n i n g ( i ) whether body form v a r i a t i o n among p o p u l a t i o n s i s i n h e r i t e d and ( i i ) t h e d e g r e e t o w h i c h body form and s i z e a r e f u n c t i o n a l l y r e l a t e d t o d i f f e r e n c e s i n swimming p e r f o r m a n c e . 6 PART 1: MORPHOMETRICS M a t e r i a l s and Methods C o l l e c t i o n of Spec imens J u v e n i l e coho were c o l l e c t e d f o r m o r p h o m e t r i c a n a l y s i s w i t h p o l e s e i n e s , minnow t r a p s and a S m i t h - R o o t Type V I I I - A e l e c t r o s h o c k e r d u r i n g 1980, 1982 and 1983. S p e c i m e n s were p r e s e r v e d i n 10 % b u f f e r e d f o r m a l i n and l a t e r t r a n s f e r r e d t o 37.5 % i s o p r o p y l a l c o h o l . I n i t i a l l y , s p e c i m e n s from t e n p o p u l a t i o n s were c o l l e c t e d f o r m o r p h o l o g i c a l a n a l y s i s ; l a t e r t h r e e of t h e s e p o p u l a t i o n s , one f r o m i n t e r i o r B.C. and two from c o a s t a l B.C. , were s u b j e c t t o f u r t h e r c o l l e c t i o n s and more d e t a i l e d s t u d y ( F i g . 1 ) . A b r i e f d e s c r i p t i o n o f t h e t h r e e s t u d y s t r e a m s i s g i v e n i n T a b l e 1. The 1980 c o l l e c t i o n s were p a r t o f a l a r g e r s t u d y ( M c P h a i l p e r s . comm.) and t h e l a t t e r c o l l e c t i o n s (1982 and 1983) were made t o d e t e r m i n e i f t h e m o r p h o l o g i c a l d i f f e r e n c e s between p o p u l a t i o n s n o t e d i n 1980 were c o n s i s t e n t o v e r t i m e . The body p a r t s measured were t h o s e t h a t o t h e r w o r k e r s have c o n s i d e r e d i m p o r t a n t i n b o t h t i m e - i n d e p e n d e n t , s u s t a i n e d swimming p e r f o r m a n c e and t i m e - d e p e n d a n t " b u r s t " o r f a s t - s t a r t , 7 F i g u r e 1. F r a s e r R i v e r System and t h e S t r a i t of G e o r g i a r e g i o n . 1 = Lemieux C r . , 2 = E. B a r r i e r e R., 3 = C o l d w a t e r R., 4 = L o u i s C r . , 5 = S i l v e r d a l e C r . , 6 = Wade C r . , 7 = Demamiel C r . , 8 = K i r b y C r . , 9 = M o r r i s o n C r . , 10 = R o s e w a l l C r . SG = S t r a i t of G e o r g i a , V = V a n c o u v e r , PG = P r i n c e G e o r g e , HG = H e l l ' s G a t e . R i v e r and c r e e k l e n g t h s a r e not t o s c a l e . U n d e r l i n i n g i n d i c a t e s s t r e a m s sampled on s u c c e s s i v e y e a r s , l a b o r a t o r y r e a r e d p o p u l a t i o n s and p o p u l a t i o n s u s e d i n swimming e x p e r i m e n t s . 9 swimming p e r f o r m a n c e (Webb 1977, 1978a, 1981; G a t z 1979; R i d d e l l and L e g g e t t 1981). Body measurements were made t o t h e n e a r e s t 0.01 mm u s i n g H e l i o s c a l i p e r s and f o l l o w Hubbs and L a g l e r (1967) e x c e p t were n o t e d ( T a b l e 2 ) . M e d i a n f i n a r e a s were e s t i m a t e d from d r a w i n g s of f i n s made w i t h a WILD H e r r b r u g g Camera L u c i d a ( m a g n i f i c a t i o n 12 X ). F i n a r e a s were t h e n c a l c u l a t e d u s i n g an APPLE II m i c r o c o m p u t e r g r a p h i c s t a b l e t . U n l e s s o t h e r w i s e s t a t e d , f o r t y i n d i v i d u a l s were measured from e a c h p o p u l a t i o n . Spawning coho were c o l l e c t e d from two p o p u l a t i o n s , t h e C o l d w a t e r R i v e r and M o r r i s o n C r e e k , t o d e t e r m i n e whether m o r p h o l o g i c a l d i f f e r e n c e s i n j u v e n i l e s were r e t a i n e d i n a d u l t s . A d u l t s were c o l l e c t e d d u r i n g November 1983 by e l e c t r o s h o c k i n g . O n l y f i s h t h a t had not d e v e l o p e d d o r s a l "humps" and were f r e e from s p a w n i n g damage ( i . e. f r a y e d f i n s ) were measured. T h e s e a d u l t s were i n d i v i d u a l l y a n a e s t h e t i s e d w i t h 2 - p h e n o x y e t h a n o l and measured i n t h e same manner as j u v e n i l e s e x c e p t f o r median f i n a r e a s . F i n a r e a s i n a d u l t s were e s t i m a t e d by m e a s u r i n g t h e a p p r o x i m a t e t r i a n g u l a r d i m e n s i o n s of e a c h f i n and l a t e r c a l c u l a t i n g t h e a r e a o f t h e t r i a n g l e . A c o m p a r i s o n o f t h i s method t o t h a t o f d r a w i n g s made w i t h a Camera L u c i d a was made on p r e s e r v e d s p e c i m e n s . The " t r i a n g u l a t i o n " method u n d e r e s t i m a t e d a c t u a l f i n a r e a s by between 10 and 15 p e r c e n t . J u v e n i l e coho from t h e upper C o l u m b i a R i v e r ( U n i v e r s i t y o f W a s h i n g t o n Museum of F i s h e r i e s ) and from c r e e k s i n n o r t h c o a s t a l B r i t i s h C o l u m b i a and A l a s k a ( U n i v e r s i t y of B.C. F i s h Museum) to T a b l e 1. B i o p h y s i c a l d e s c r i p t i o n of t h e n a t a l s t r e a m s o f t h e t h r e e s t u d y p o p u l a t i o n s . C h a r a c t e r i s t i c M o r r i s o n C r . Wade C r . C o l d w a t e r R. L o n g i t u d e 125 00 45 W 122 10 39 W 120 55 42 W L a t i t u d e 49 41 30 N 49 07 55 N 49 59 04 N D i s t a n c e f r o m sea (km) 4.5 82 673 L e n g t h (km) 6.4 5. 1 71 D r a i n a g e A r e a ( s q km) 17.5 10.3 914.5 T e m p e r a t u r e ( r a n g e ,* C) 5.0-17.5 2.0-15.5 0-17.5 D i s c h a r g e (mean annual,m / s ) 1.84 0.38 7.32 PH ( r a n g e ) 7.36-7.93 6.36-7.18 6.91-7.41 C o n d u c t i v i t y (uhoms-25*C) 229.8-351.8 26.7-49.5 55.7-132.4 O t h e r f i s h e s Salmo c l a r k i c l a r k i  S. q a i r d n e r i  Q n c o r h y n c h u s k e t a O. q o r b u s c h a  C o t t u s a s p e r C. a l e u t i c u s  L"ampetra s p . Salmo c . d a r k i S. qa i r d n e r i S. q a i r d n e r i S a l v e l i n u s c o n f l u e n t u s O. t s h a w y t s c h a p_. t s h a w y t s c h a O. k e t a C. c o g n a t u s C_. a s p e r C_. a s p e r P r o s o p i u m w i l l i a m s o n i  C a t o s t o m u s c o l u m b i a n u s R h i n i c h t h y s f a l c a t u s  R. c a t a r a c t a e  L a m p e t r a s p . M a j o r Land Use P a r k , f a r m l a n d , l o w d e n s i t y r e s . Wooded F a r m l a n d and low d e n s i t y r e s i -d e n t i a l i n l o w e r r e a c h e s , a c t i v e l o g g i n g i n upper r e a c h e s 11 were measured and a n a l y s e d t o see i f t h e m o r p h o l o g i c a l d i f f e r e n c e s between i n t e r i o r and c o a s t a l p o p u l a t i o n s i n t h e F r a s e r R i v e r and s o u t h e r n B.C. a l s o o c c u r r e d i n o t h e r a r e a s . B r e e d i n g e x p e r i m e n t s To d e t e r m i n e whether t h e m o r p h o l o g i c a l d i f f e r e n c e s a p p a r e n t i n w i l d samples a r e i n p a r t i n h e r i t e d , t h r e e p o p u l a t i o n s were r e a r e d i n t h e l a b o r a t o r y under i d e n t i c a l c o n d i t i o n s . Eggs and m i l t were c o l l e c t e d f r o m r i p e a d u l t s i n M o r r i s o n C r e e k ( t h r e e f e m a l e s X t h r e e m a l e s ) , Wade C r e e k (two f e m a l e s X two m a l e s ) and C o l d w a t e r R i v e r ( f o u r f e m a l e s X t h r e e m a l e s ) . The eggs were f e r t i l i z e d i n t h e f i e l d , t r a n s p o r t e d t o t h e l a b o r a t o r y and t h e n i n c u b a t e d under c o n t r o l l e d c o n d i t i o n s i n an a p p a r a t u s d e s c r i b e d by M u r r a y ( 1 9 8 0 ) . A sample of a t l e a s t s i x t y eggs was t a k e n f r o m e a c h p o p u l a t i o n and p r e s e r v e d i n 10 % b u f f e r e d f o r m a l i n . Egg v o l u m e s were d e t e r m i n e d by d i s p l a c e m e n t . D u r i n g i n c u b a t i o n , egg b a s k e t s were " p i c k e d " o f dead eggs e v e r y t h r e e d a y s up t o t h e " e y e d " s t a g e . A f t e r t h i s s t a g e dead eggs and a l e v i n s were removed e a c h day u n t i l emergence. The t e m p e r a t u r e c o n t r o l o s y s t e m was s e t f o r 4 C and t h e a v e r a g e i n c u b a t i o n t e m p e r a t u r e o was 3.95 + 0.51 C o v e r t h e f i v e month i n c u b a t i o n p e r i o d . Emergence was d e t e r m i n e d u s i n g Mason's (1976) " c h o i c e box" 12. T a b l e 2 M o r p h o m e t r i c measurements u s e d i n t h e s t u d y . Measurement Symbol Def i n i t i o n S t a n d a r d l e n g t h Body d e p t h C a u d a l p e d u n c l e d e p t h C a u d a l p e d u n c l e l e n g t h D o r s a l f i n A r e a A n a l f i n a r e a C a u d a l f i n a r e a T o t a l median f i n a r e a P e c t o r a l f i n l e n g t h P e l v i c f i n l e n g t h S n o u t - a n t e r i o r i n s e r t i o n P e c f S n o u t - a n t e r i o r i n s e r t i o n P e l v f Mean of Bodyd and max body w i d t h F i n e n e s s r a t i o Head l e n g t h Head d e p t h SL Hubbs and L a g l e r (1967) Bodyd I b i d Pedd I b i d P e d l I b i d DFA A r e a bounded by f i n m a r g i n s AFA As above CFA As above TMFA Sum of DFA, AFA and CFA P e c f Hubbs and L a g l e r (1967) P e l v f I b i d SNAP R i d d e l l and L e g g e t t (1981) SNAPE I b i d BWBD G a t z (1979) FR I b i d HL Hubbs and L a g l e r (1967) HD I b i d 13 t e c h n i q u e . When 40 p e r c e n t , or more, of t h e t e s t f i s h were p h o t o p o s i t i v e t h e p o p u l a t i o n was c o n s i d e r e d emerged and a l l t h e f i s h were removed from t h e i n c u b a t o r s and p l a c e d i n r e a r i n g t r o u g h s ( s e e below) where t h e y were a l l o w e d a f u r t h e r 24 h o u r s t o c o m p l e t e emergence. A f t e r t h i s p e r i o d , a sample of t h i r t y newly emerged f r y was a n a e s t h e t i s e d w i t h 2 - p h e n o x y e t h a n o l and s t a n d a r d l e n g t h s and w e i g h t s t o t h e n e a r e s t 0.5 mm and 0.01 gm were r e c o r d e d . R e a r i n g and M a i n t e n a n c e of W i I d and L a b o r a t o r y P o p u l a t i o n s W i l d and l a b o r a t o r y r e a r e d j u v e n i l e s were m a i n t a i n e d i n s e p a r a t e 92.5 l i t r e r e c t a n g u l a r r e a r i n g t r o u g h s . E a c h t r o u g h was s u p p l i e d w i t h a c o n s t a n t f l o w of a p p r o x i m a t e l y 4.5 l i t r e s / m i n u t e of d e c h l o r i n a t e d w a t e r . T e m p e r a t u r e s d u r i n g t h e o r e a r i n g p e r i o d f l u c t u a t e d s e a s o n a l l y from 4.0 C i n J a n u a r y t o o 13.5 C i n September. F o r t h e f i r s t two weeks f r y were f e d ad  1 i b i t u r n on an e q u a l m i x t u r e o f g r o u n d C l a r k ' s New Age c o m m e r c i a l h a t c h e r y f o o d and T e t r a m i n a q u a r i u m f i s h f o o d . T h e r e a f t e r , f i s h were f e d t h r e e t i m e s d a i l y on g r o u n d C l a r k ' s f o o d . I n d i v i d u a l r e a r i n g t r o u g h s were i l l u m i n a t e d by s i n g l e 40 watt c o o l - w h i t e f l u o r e s c e n t l i g h t s s e t t o a l i g h t : d a r k c y c l e t h a t f o l l o w e d t h e n a t u r a l p h o t o p e r i o d . Growth was m o n i t o r e d i n e a c h p o p u l a t i o n a t m o n t h l y i n t e r v a l s by r e c o r d i n g l e n g t h s and w e i g h t s from a sample 14 of t h i r t y f i s h . When t h e mean s t a n d a r d l e n g t h r e a c h e d a p p r o x i m a t e l y 50 mm a t e s t g r o u p was removed f o r swimming e x p e r i m e n t s . A t t h i s t i m e f o r t y i n d i v i d u a l s from e a c h p o p u l a t i o n were p r e s e r v e d i n 10 % b u f f e r e d f o r m a l i n and s t o r e d f o r m o r p h o m e t r i c a n a l y s i s . S t a t i s t i c a l methods T r e a t m e n t o f a l l m o r p h o l o g i c a l d a t a i n v o l v e d s t a n d a r d i z a t i o n o f body measurements t o an o v e r a l l sample mean s t a n d a r d l e n g t h ( T h o r p e 1976; I h s s e n e_t a l . 1981; R i d d e l l and L e g g e t t 1981). L o g a r i t h m i c a l l y (base, 0) t r a n s f o r m e d measurements were r e g r e s s e d a g a i n s t t h e l o g a r i t h m of s t a n d a r d l e n g t h i n e a c h p o p u l a t i o n and t h e r e s u l t a n t s l o p e s u s e d t o c a l c u l a t e t h e s t a n d a r d i z e d d a t a s e t . The p r o c e d u r e f o l l o w s S t e e l and T o r r i e (1980) and t h e s t a n d a r d i z a t i o n f o r m u l a i s : Y' = l o g Y - b * ( l o g X - l o g X ) (1) Were Y' = t h e a d j u s t e d body measurement, Y = o r i g i n a l body measurement, X = s t a n d a r d l e n g t h , b = r e g r e s s i o n c o e f f i c i e n t f o r l o g Y on l o g X and l o g X = mean l o g o f X v a l u e s ( s t a n d a r d 15 l e n g t h s ) . T h i s p r o c e d u r e m i n i m i z e s d i f f e r e n c e s i n body measurements due t o a l l o m e t r y and d i f f e r e n c e s i n mean s t a n d a r d l e n g t h between samples and t h u s a l l o w s d i r e c t c o m p a r i s o n of body measurements ( i . e. body shape) among s a m p l e s . In a l l s u b s e q u e n t m o r p h o l o g i c a l a n a l y s e s , t h e a n t i l o g s of t h e s t a n d a r d i z e d d a t a were u s e d . I n i t i a l a n a l y s e s u s e d s i n g l e c l a s s i f i c a t i o n ANOVAS ( S o k a l and R o h l f 1969) w i t h B a r t l e t t ' s t e s t f o r h o m o g e n e i t y o f sample v a r i a n c e s and S c h e f f e ' s t e s t f o r m u l t i p l e g r o u p c o m p a r i s o n s . A Spearman rank c o r r e l a t i o n c o e f f i c i e n t ( S o k a l and R o h l f 1969) was c a l c u l a t e d between E u c l i d e a n d i s t a n c e (a measure of d i s s i m i l a r i t y , P i m e n t e l 1979) measures of d i f f e r e n c e s among c h a r a c t e r means and g e o g r a p h i c d i s t a n c e s between p o p u l a t i o n s . A c a r t o m e t e r was us e d t o d e t e r m i n e g e o g r a p h i c d i s t a n c e s between n a t a l r i v e r mouths from t o p o g r a p h i c maps. S t e p w i s e d i s c r i m i n a n t f u n c t i o n a n a l y s i s (BMDP:7M, D i x o n 1981) was u s e d t o d e f i n e o v e r a l l m o r p h o l o g i c a l v a r i a t i o n among p o p u l a t i o n s , or p o p u l a t i o n g r o u p s , and t o i d e n t i f y t h e c h a r a c t e r i s t i c s t h a t b e s t d i f f e r e n t i a t e d g r o u p s . The W i l k s ' lambda, and i t s a p p r o x i m a t e t r a n s f o r m a t i o n t o t h e F s t a t i s t i c were t h e c r i t e r i a u s e d t o t e s t f o r s i g n i f i c a n t d i f f e r e n c e s between g r o u p c e n t r o i d s . H o mogeneity o f sample c o v a r i a n c e m a t r i c e s was t e s t e d by Box's t e s t (Fox and G u l r e 1976). C o n f i d e n c e l i m i t s f o r g r o u p c e n t r o i d s were c a l c u l a t e d a s o u t l i n e d i n S e a l (1964, p. 2 4 ) . Spearman rank c o r r e l a t i o n c o e f f i c i e n t s were c a l c u l a t e d 16 between t h e means of m o r p h o l o g i c a l t r a i t s f o r e a c h p o p u l a t i o n and d i s t a n c e t o t h e sea from t h e p r i m a r y n a t a l s t r e a m s . D i s t a n c e f r o m uppermost spawning t o t h e s e a was d e t e r m i n e d from S t r e a m s i d e F i s h e r y O f f i c e r R e p o r t s ( C a n a d i a n D epartment of F i s h e r i e s and Oceans, V a n c o u v e r ) and t o p o g r a p h i c maps. Water t e m p e r a t u r e and d i s c h a r g e d a t a were o b t a i n e d f r o m Water S u r v e y of Canada r e c o r d s o r by u s i n g F i s h e r b r a n d p o c k e t t h e rmometers and by t a k i n g c u r r e n t and d e p t h measurements a l o n g a s t r e a m p r o f i l e . C o n d u c t i v i t y r e a d i n g s and pH were r e c o r d e d u s i n g a F i s h e r 119 pH meter and a Bach-Simpson Type CDM 2d c o n d u c t i v i t y meter d u r i n g r e g u l a r c o l l e c t i o n p e r i o d s . R e s u l t s M o r p h o m e t r i e s of J u v e n i l e s from W i l d P o p u l a t i o n s Coho salmon d i s p l a y a h i g h d e g r e e o f m o r p h o l o g i c a l h e t e r o g e n e i t y ( A p p e n d i x T a b l e A . 1 ) . S c h e f f e ' s m u l t i p l e g r o u p t e s t (ANOVA) i n d i c a t e d t h a t o u t of f o r t y - f i v e p o s s i b l e p a i r w i s e c o m p a r i s o n s of a d j u s t e d mean v a l u e s f o r e a c h o f f i f t e e n c h a r a c t e r i s t i c s , f o r t y - f o u r r e s u l t e d i n s i g n i f i c a n t d i f f e r e n c e s a t t h e 5 p e r c e n t l e v e l (F{9,390} range = 3.32-59.11) f o r a t l e a s t one c h a r a c t e r . O n l y two i n t e r i o r s t r e a m s , L o u i s C r e e k and C o l d w a t e r R i v e r , were not d i f f e r e n t ( f r o m e a c h o t h e r ) i n any of t h e f i f t e e n c h a r a c t e r s e xamined. The f r e q u e n c y of s i g n i f i c a n t d i f f e r e n c e s and t h e m a g n i t u d e of t h e d i f f e r e n c e s t e n d e d t o be 17 h i g h e r f o r c o a s t a l - i n t e r i o r p o p u l a t i o n c o m p a r i s o n s t h a n between c o a s t a l - c o a s t a l o r i n t e r i o r - i n t e r i o r c o m p a r i s o n s . The r e s u l t s of a t e n g r o u p d i s c r i m i n a n t f u n c t i o n a n a l y s i s a r e summarized i n F i g . 2. M u l t i v a r i a t e a n a l y s i s o f v a r i a n c e i n d i c a t e d s i g n i f i c a n t d i f f e r e n c e s i n a l l p a i r w i s e c o m p a r i s o n s of p o p u l a t i o n c e n t r o i d s ( r a n g e F{12,408}= 4.19-62.58). A g a i n , however, c o a s t a l s a m p l e s t e n d e d t o be more s i m i l a r t o o t h e r c o a s t a l s a m p l e s t h a n t o i n t e r i o r samples and v i c e v e r s a ( A p p e n d i x T a b l e A . 2 ) . D i s c r i m i n a n t f u n c t i o n a n a l y s i s u s i n g j a c k k n i f e d c l a s s i f i c a t i o n p r o c e d u r e ( I h s s e n e t a l . 1981) r e s u l t e d i n i n t e r i o r s p e c i m e n s b e i n g c o r r e c t l y c l a s s i f i e d a s t o r i v e r o f o r i g i n w i t h between 80 and 97 p e r c e n t a c c u r a c y (mean 88 p e r c e n t ) . In c o n t r a s t , c l a s s i f i c a t i o n of l o w e r F r a s e r V a l l e y and c o a s t a l f i s h was l e s s s u c c e s s f u l (means = 54 and 62 p e r c e n t r e s p e c t i v e l y ) . O v e r a l l , 71 p e r c e n t of i n d i v i d u a l coho from t h e t e n p o p u l a t i o n s were c o r r e c t l y c l a s s i f i e d t o t h e i r r i v e r o f o r i g i n . The p o o r e r c l a s s i f i c a t i o n s u c c e s s i n c o a s t a l p o p u l a t i o n s s u g g e s t s t h a t t h e r e i s g r e a t e r m o r p h o l o g i c a l v a r i a t i o n among t h e s e p o p u l a t i o n s (and t h u s more i n t e r p o p u l a t i o n o v e r l a p ) , l e s s d i f f e r e n c e s among means o r b o t h . C e r t a i n c o a s t a l p o p u l a t i o n p a i r s w h i c h were g e o g r a p h i c a l l y c l o s e t o e a c h o t h e r ( e . g. M o r r i s o n C r e e k - R o s e w a l l C r e e k , Demamiel C r e e k - K i r b y C r e e k , Wade C r e e k - S i l v e r d a l e C r e e k ) were t h e most f r e q u e n t l y m i s c l a s s i f i e d ( u s u a l l y w i t h e a c h o t h e r ) and MANOVA s i g n i f i c a n c e l e v e l s between t h e s e p a i r s were u s u a l l y l o w e r t h a n i n g e n e r a l p o p u l a t i o n c o m p a r i s o n s . G e o g r a p h i c d i s t a n c e between a l l 18 F i g u r e 2. D i s c r i m i n a n t f u n c t i o n a n a l y s i s d e s c r i b i n g m o r p h o l o g i c a l v a r i a t i o n among t e n p o p u l a t i o n s of j u v e n i l e c oho salmon. N u m e r a l s i n d i c a t e p o s i t i o n o f p o p u l a t i o n c e n t r o i d s ( + 95 % c o n f i d e n c e l i m i t s ) , 1 = Lemieux C r . , 2 = E. B a r r i e r e C r . , 3 = C o l d w a t e r R. , 4 = L o u i s C r . , 5 = S i l v e r d a l e C r . , 6 = Wade C r . , 7 = Demamiel C r . , 8 = K i r b y C r . , 9 = M o r r i s o n C r . , 10 = R o s e w a l l C r . E q u a t i o n s 5-7 a r e s t a n d a r d i z e d d i s c r i m i n a n t f u n c t i o n s e x p l a i n i n g 84 p e r c e n t o f t h e t o t a l v a r i a n c e , R L i s p r o p o r t i o n of t o t a l v a r i a n c e a c c o u n t e d f o r by i n t e r p o p u l a t i o n d i f f e r e n c e s . The p e r c e n t a g e v a r i a n c e a l o n g e a c h a x i s i s t h e p e r c e n t a g e o f th e e x p l a i n e d v a r i a n c e a c c o u n t e d f o r by e a c h a x i s . (5) DF 1.77 Bodyd + 1.73 DFA - 4.47 AFA - 3.48 TMFA - 3 . 1 BWBD + 1.53 HL 1 1 .99 R2" = 0.76 (6) DF 3.56 DFA - 9.76 AFA - 2.62 Bodyd - 1.55 SNAP + 2.94 BWBD + 1.88 HL - 3.29 R7" = 0.66 (7) DF 0.63 Pedd - 0.96 DFA 4.84 TMFA + 0.89 BWBD - 1.14 HL + 10.70 R 1 = 0.51 20 p o p u l a t i o n s was s i g n i f i c a n t l y , a l b e i t w e a k l y , c o r r e l a t e d w i t h m o r p h o l o g i c a l ( E u c l i d e a n ) d i s t a n c e ( r = 0.41, df = 43, P < 0.01). When c a n o n i c a l v a r i a b l e s a l o n g t h e f i r s t c a n o n i c a l a x i s f o r i n d i v i d u a l s f r o m e a c h p o p u l a t i o n ( F i g . 2) were p a i r e d a g a i n s t d i s t a n c e from t h e sea a s i g n i f i c a n t c o r r e l a t i o n was o b t a i n e d ( r = .56, P < 0.0001) s u g g e s t i n g t h e e x i s t a n c e of a c o a s t a l - i n t e r i o r m o r p h o l o g i c a l c l i n e ( G o u l d and J o h n s t o n 1972). When t h e p o p u l a t i o n s were g r o u p e d a s e i t h e r c o a s t a l o r i n t e r i o r and t h e n compared a l l o f t h e c o m p a r i s o n s were s i g n i f i c a n t ( T a b l e 3 ) . T h i s s u g g e s t s t h a t t h e r e a r e c o n s i s t e n t m o r p h o l o g i c a l d i f f e r e n c e s between c o a s t a l and i n t e r i o r p o p u l a t i o n s . G e n e r a l l y , c o a s t a l coho have d e e p e r b o d i e s and c a u d a l p e d u n c l e s , l o n g e r c a u d a l p e d u n c l e s and a g r e a t e r d i s t a n c e f r o m t h e s n o u t t o t h e a n t e r i o r i n s e r t i o n of t h e p e c t o r a l f i n (SNAP), g r e a t e r median f i n a r e a s , s h o r t e r p a i r e d f i n s and a s h o r t e r d i s t a n c e form t h e s n o u t t o t h e a n t e r i o r i n s e r t i o n of t h e p e l v i c f i n (SNAPE), more r o b u s t b o d i e s ( h i g h e r BWBD, l o w e r FR) and s h o r t e r , s h a l l o w e r heads t h a n coho from i n t e r i o r p o p u l a t i o n s ( F i g . 3 ) . As i n d i c a t e d by t h e c o n s i s t e n t l y h i g h e r c o e f f i c i e n t s o f v a r i a t i o n i n t h e c o a s t a l g r o u p , t h e g r o u p i n g p r o c e d u r e a l s o s u g g e s t s t h a t w i t h i n - g r o u p m o r p h o l o g i c a l v a r i a t i o n i s h i g h e r i n t h e c o a s t a l p o p u l a t i o n s . R e s u l t s o f a two-group d i s c r i m i n a n t f u n c t i o n a n a l y s i s a r e shown i n F i g . 4. A p r i o r i g r o u p i n g of t h e l o w e r F r a s e r R i v e r V a l l e y p o p u l a t i o n s w i t h t h e V a n c o u v e r I s l a n d p o p u l a t i o n s a s t h e 2.1 T a b l e 3. A d j u s t e d g e o m e t r i c means o f measurements and r e s u l t s o f ANOVA c o m p a r i n g p o o l e d c o a s t a l a nd i n t e r i o r p o p u l a t i o n s . V a l u e s a r e means ( + SD, mm). C h a r a c t e r s have been a d j u s t e d t o o v e r a l l sample mean s t a n d a r d l e n g t h of 52mm. A b b r e v i a t i o n s a r e a s i n T a b l e 2. F i n a r e a s a r e i n s q mm. Measurement C o a s t a l I n t e r i o r F{1,389} P N 236 155 Bodyd 12.38 ( .63) 11.35 ( .52) 1 49. 2 < 0. 001 Pedd 4.99 ( .32) 4.72 ( .23) 93. 2 < 0. 001 P e d l 14.25 ( .48) 13.91 ( .43) 53. 7 < 0. 001 DFA 34.96 (6 .41 ) 29.72 (5 .98) 75. 6 < 0. 001 AFA 31.06 (5 .30) 25.42 (5 .28) 148. 8 < 0. 01 CFA 84.53 (14 .22) 76.63 (11 .91 ) 33. 1 < 0. 001 TMFA 151.65 (23 .64) 132.01 (19 .30) 75. 3 < 0. 001 P e c f 8.46 ( .53) 8.59 ( .43) 7. 1 < 0. 01 P e l v f 6.70 ( .41 ) 6.81 ( .35) 8. 1 < 0. 01 SNAP 12.48 ( .53) 1 2.35 ( .51 ) 5. 7 < 0. 01 SNAPE 25.87 ( .90) 26. 15 ( .63) 1 1 . 3 < 0. 05 BWBD 9.36 ( .60) 8.91 ( .49) 78. 9 < 0. 01 FR 5. 12 ( .29) 5.36 ( .27) 67. 3 < 0. 001 HL 13.91 ( .57) 1 4.25 ( .52) 35. 7 < 0. 001 HD 9.08 ( .32) 9.27 ( .46) 20. 9 < 0. 001 22 F i g u r e 3. P h o t o g r a p h of r e p r e s e n t a t i v e c o a s t a l ( u p p e r -M o r r i s o n C r e e k ) and i n t e r i o r ( l o w e r - C o l d w a t e r R i v e r ) j u v e n i l e c oho s a l m o n . S c a l e b a r r e p r e s e n t s 10 mm. Z3 24 F i g u r e 4. Two-group d i s c r i m i n a n t f u n c t i o n a n a l y s i s d e s c r i b i n g m o r p h o l o g i c a l v a r i a t i o n between c o a s t a l ( ) and i n t e r i o r ( ) w i l d c oho salmon p o p u l a t i o n s . C = C o a s t a l , I = I n t e r i o r g r o u p means (± 95 % c o n f i d e n c e i n t e r v a l s ) . E q u a t i o n 8 i s a s t a n d a r d i z e d d i s c r i m i n a n t f u n c t i o n , R*" i s p r o p o r t i o n of t o t a l v a r i a n c e a c c o u n t e d f o r by i n t e r g r o u p d i f f e r e n c e s . (8) DF = 9.2 CFA + 7.0 AFA - 10.25 TMFA + 1.74 HL - 1.28 Bodyd - 1.08 Pedd - 7.43 R Z = 0.63 Z 5 26 " c o a s t a l " g r o u p r e s u l t e d i n h i g h e r p e r c e n t c o r r e c t c l a s s i f i c a t i o n and i n g r e a t e r s t a t i s t i c a l s i g n i f i c a n c e of d i f f e r e n c e s between g r o u p means (81.2 vs 92.8 p e r c e n t and F{8,382}=32.6 v s F{7,383}=94.5) t h a n when t h e s e p o p u l a t i o n s were i n c l u d e d i n t h e " i n t e r i o r " g r o u p . Thus, Lower F r a s e r V a l l e y p o p u l a t i o n s a p p e a r t o m o r p h o l o g i c a l l y r e s e m b l e V a n c o u v e r I s l a n d p o p u l a t i o n s more c l o s e l y t h a n t h e y do upper F r a s e r R i v e r p o p u l a t i o n s . The most p o w e r f u l c h a r a c t e r s d i s c r i m i n a t i n g c o a s t a l and i n t e r i o r p o p u l a t i o n s a r e , i n o r d e r o f d e c r e a s i n g i m p o r t a n c e : t o t a l median f i n a r e a , c a u d a l f i n a r e a , a n a l f i n a r e a , head l e n g t h , body d e p t h and p e d u n c l e d e p t h . In summary, coho salmon f r o m t e n p o p u l a t i o n s i n t h e F r a s e r R i v e r and a d j a c e n t a r e a s of t h e S t r a i t of G e o r g i a r e g i o n c a n be c l a s s i f i e d i n t o " c o a s t a l " and " i n t e r i o r " m o r p h o l o g i c a l g r o u p s . I n d i v i d u a l s f r o m component p o p u l a t i o n s w i t h i n e a c h g r o u p can be c o r r e c t l y c l a s s i f i e d as e i t h e r c o a s t a l o r i n t e r i o r w i t h 93 p e r c e n t a c c u r a c y . Most of t h e m i s c l a s s i f i c a t i o n i n v o l v e d c o a s t a l i n d i v i d u a l s m i s c l a s s i f i e d a s i n t e r i o r (11 p e r c e n t ) . In c o n t r a s t , o n l y t h r e e i n t e r i o r i n d i v i d u a l s ( < 2 p e r c e n t ) were m i s c l a s s i f i e d as c o a s t a l f i s h ( F i g . 4 ) . C o a s t a l and i n t e r i o r p o p u l a t i o n s d i f f e r i n a number o f m o r p h o l o g i c a l f e a t u r e s of w h i c h median f i n a r e a s and f e a t u r e s of body " r o b u s t n e s s " a r e t h e most s i g n i f i c a n t and t h e c o a s t a l f i s h a r e c h a r a c t e r i z e d by h i g h e r g e n e r a l i z e d v a r i a n c e (a c o m p o s i t e of a l l c h a r a c t e r s ) . To t e s t t h e power of t h e c o a s t a l - i n t e r i o r d i s c r i m i n a n t 27 f u n c t i o n , i n d i v i d u a l j u v e n i l e c oho from t h e upper C o l u m b i a s y s t e m , n o r t h c o a s t a l B.C., t h e Queen C h a r l o t t e I s l a n d s ' and A l a s k a ( T a b l e 4) were measured and a d j u s t e d t o mean s t a n d a r d l e n g t h . T h e s e i n d i v i d u a l s were t h e n c l a s s i f i e d u s i n g t h e " c o a s t a l - i n t e r i o r " d i s c r i m i n a n t f u n c t i o n ( e q u a t i o n 8, F i g . 4 ) . Ten out of t h i r t e e n c o a s t a l samples were c o r r e c t l y c l a s s i f i e d as c o a s t a l (77. p e r c e n t ) and s i x o u t of s e v e n upper C o l u m b i a j u v e n i l e s were c o r r e c t l y c l a s s i f i e d as i n t e r i o r (86 p e r c e n t ) . T h i s s u g g e s t s t h a t t h e " c o a s t a l - i n t e r i o r " s t o c k s e p a r a t i o n t y p i c a l o f t h e F r a s e r R i v e r - S t r a i t of G e o r g i a a r e a i s p a r t o f a c o a s t - w i d e p a t t e r n . A summary o f t h e u n i v a r i a t e ANOVAS between t h e t h r e e p o p u l a t i o n s t h a t were s t u d i e d i n d e t a i l i s g i v e n i n t h e A p p e n d i x ( T a b l e A.3, A . 4 ) . The 1982 samples p r o d u c e d s i g n i f i c a n t d i f f e r e n c e s i n 66 p e r c e n t (30/45) o f a l l p o s s i b l e c o m p a r i s o n s whereas t h e 1983 s a m p l e s r e s u l t e d i n 40 p e r c e n t ( 2 0 / 4 5 ) . The s i g n i f i c a n t i n t e r p o p u l a t i o n d i f f e r e n c e s i n o v e r a l l body shape e v i d e n t i n t h e 1982 s a m p l e s were m a i n t a i n e d i n t h e 1983 samples (MANOVA minimum F{8,110}=29.8 and F{6,112}=17.1 r e s p e c t i v e l y ) . In b o t h 1982 and 1983 head l e n g t h s and f e a t u r e s of body r o b u s t n e s s were t h e dominant m o r p h o l o g i c a l f e a t u r e s d i f f e r e n t i a t i n g t h e t h r e e p o p u l a t i o n s ( F i g . 5, 6 ) . J a c k k n i f e d c l a s s i f i c a t i o n p r o c e d u r e c o r r e c t l y i d e n t i f i e d s p e c i m e n s from t h e i r n a t i v e r i v e r w i t h 93 p e r c e n t a c c u r a c y (range:90-98 p e r c e n t ) i n 1982 and w i t h 87 p e r c e n t a c c u r a c y ( r a n g e 80-98 p e r c e n t ) i n 1983. F o r e a c h o f t h e f i f t e e n c h a r a c t e r s t h e 28 T a b l e 4. C l a s s i f i c a t i o n r e s u l t s u s i n g j u v e n i l e c oho s p e c i m e n s f r o m n o r t h c o a s t a l - B.C., A l a s k a and t h e u p p e r C o l u m b i a R i v e r s y s t e m . C u t o f f d i s c r i m i n a n t s c o r e i s m i d p o i n t between c o a s t a l - i n t e r i o r g r o u p means, = 0.388 (s e e F i g . 4 ) . A s t e r i s k i n d i c a t e s c l a s s i f i c a t i o n e r r o r L o c a t i o n D i s c r i m i n a n t S c o r e C l a s s i f i c a t i o n C o a s t a l Unnamed (Q.C.I.) H II n ?i II II n II II »i II it Unnamed ( J u s k a t l a I n l e t ) II n it M a r t i n R. (Ocean F a l l s ) A g a t t u I s l a n d ( A l a s k a ) G o l d C r . (Q.C.I.) G o l d C r . (Q.C.I.) Bear Lake (Van. I s i . ) G i l l i e s Bay C r . (Texada I s . ) I n t e r i o r Salmon R. ( C o l u m b i a R.) War C r . ( C o l u m b i a R.) »! II II II II II II II II II II II i i i i n -0.85 C o a s t a l 0.35 C o a s t a l -0.98 C o a s t a l -0.55 C o a s t a l 0.37 C o a s t a l -2.07 . C o a s t a l -0.74 C o a s t a l 0.42 * I n t e r i o r 0.36 C o a s t a l 2.72 * I n t e r i o r -0.75 C o a s t a l 3.06 * I n t e r i o r 0.09 C o a s t a l 3.70 I n t e r i o r 1.71 I n t e r i o r . 3.34 I n t e r i o r 1.76 I n t e r i o r 0.99 I n t e r i o r 1.44 I n t e r i o r 0.37 * C o a s t a l 29 p o p u l a t i o n a d j u s t e d means were r a n k e d from one t o t h r e e i n o r d e r of d e c r e a s i n g m a g n i t u d e . T h i s made p o s s i b l e a t o t a l of f o r t y -f i v e r a n k i n g c o m p a r i s o n s ( A p p e n d i x T a b l e A . 6 ) . T h i r t y - t h r e e p e r c e n t (15/45) of t h e r a n k s were t h e same i n 1983 as i n 1982. The c h a r a c t e r s w h i c h d i s p l a y e d t h e g r e a t e s t between y e a r s c o n s i s t e n c y i n r e l a t i v e m a g n i t u d e were body d e p t h , p e d u n c l e d e p t h , BWBD and f i n e n e s s r a t i o . S i n c e i n t e r p o p u l a t i o n d i f f e r e n c e s i n body form were m a i n t a i n e d o v e r s u c e s s i v e y e a r s , t h a t t h e m o r p h o l o g i c a l d i s c r e t e n e s s i n d i c a t e d t h e m u l t i v a r i a t e a n a l y s i s i s p r o b a b l y p a r t i a l l y i n h e r i t e d . S h i f t i n g of c e n t r o i d s , or i n d i v i d u a l c h a r a c t e r r a n k , between y e a r s may be due t o y e a r - t o - y e a r e n v i r o n m e n t a l m o d i f i c a t i o n o f o v e r a l l m o r p h o l o g y ( R i d d e l l and L e g g e t t 1981). The c h a n g e s i n t h e r e l a t i v e r a n k i n g of c h a r a c t e r s between y e a r s , however, s u g g e s t s t h a t t h e c o r r e s p o n d e n c e between b r o o d y e a r s i n c e r t a i n t r a i t s may be low ( e . g. f i n a r e a s and l e n g t h s ) . M o r p h o m e t r i e s o f L a b o r a t o r y R e a r e d P o p u l a t i o n s The ANOVAS and r e l a t i v e r a n k i n g o f e a c h v a r i a b l e - f o r t h e t h r e e p o p u l a t i o n i n c u b a t e d and r e a r e d i n t h e l a b o r a t o r y a r e d e t a i l e d i n t h e A p p e n d i x ( T a b l e A . 5 ) . The r e s u l t s of t h i s e x p e r i m e n t a r e s i m i l a r t o t h e i n t e r y e a r r e s u l t s . The s i g n i f i c a n t d i f f e r e n c e s between p o p u l a t i o n c e n t r o i d s i n w i l d samples were m a i n t a i n e d i n t h e l a b o r a t o r y p o p u l a t i o n s r e a r e d under t h e same c o n t r o l l e d c o n d i t i o n s (MANOVA minimum 30 F i g u r e 5. D i s c r i m i n a n t f u n c t i o n a n a l y s i s d e s c r i b i n g m o r p h o l o g i c a l v a r i a t i o n among w i l d j u v e n i l e c oho from t h e t h r e e s t u d y p o p u l a t i o n s , 1982. Num e r a l s i n d i c a t e p o p u l a t i o n c e n t r o i d s ( ± 95 % c o n f i d e n c e l i m i t s ) , 1 = C o l d w a t e r R., 2 = M o r r i s o n C r . , 3 = Wade C r . E q u a t i o n s (9) and (10) a r e s t a n d a r d i z e d d i s c r i m i n a n t f u n c t i o n s , R1" i s p r o p o r t i o n o f t o t a l v a r i a n c e a c c o u n t e d f o r by i n t e r p o p u l a t i o n d i f f e r e n c e s . The p e r c e n t a g e v a r i a n c e a l o n g e a c h a x i s i s t h e p e r c e n t a g e of t h e e x p l a i n e d v a r i a n c e a c c o u n t e d f o r by e a c h a x i s . (9) DF = 9.44 DFA + 2.14 TMFA - 1.65 Pedd - 2.09 P e l v - 1.07 HL + 32.97 0.80 (10) DF 1.23 HL + 0.95 BWBD - 6.79 DFA 2.33 TMFA + 1.33 Pedd - 15.00 0.67 3\ 65% T.V. 32 F i g u r e 6. D i s c r i m i n a n t f u n c t i o n a n a l y s i s d e s c r i b i n g m o r p h o l o g i c a l v a r i a t i o n among w i l d j u v e n i l e c oho from t h e t h r e e s t u d y p o p u l a t i o n s , 1983. Nume r a l s i n d i c a t e p o p u l a t i o n c e n t r o i d s ( +. 95 % c o n f i d e n c e l i m i t s ) , 1 = C o l d w a t e r R., 2 = M o r r i s o n C r . , 3 = Wade C r . E q u a t i o n s 11 and 12 a r e s t a n d a r i z e d d i s c r i m i n a n t f u n c t i o n s , R v i s p r o p o r t i o n o f v a r i a n c e a c c o u n t e d f o r by i n t e r p o p u l a t i o n d i f f e r e n c e s . The p e r c e n t a g e v a r i a n c e a l o n g e a c h a x i s i s t h e p e r c e n t a g e of t h e e x p l a i n e d v a r i a n c e a c c o u n t e d f o r by e a c h a x i s . (11) DF = 8.9 FR + 2.45 BWBD + 1.37 HL - 0.92 Bodyd + 0.96 HD + 0.15 P e d l - 92.27 R V = 0.86 (12) Y = 2.97 P e d l -0.98 Bodyd - 4.87 BWBD - 11.5 FR - 0.04 HL - 1.61 HD + 115.54 R*" = 0.35 33 3 2 I-93% T.V. 34 F{5,113}=18.5, P < 0.001). A g a i n t h i s s u g g e s t s t h a t t h e i n t e r p o p u l a t i o n m o r p h o l o g i c a l d i f f e r e n c e s f o u n d i n j u v e n i l e coho a r e a t l e a s t p a r t l y g e n e t i c . D i s c r i m i n a n t f u n c t i o n a n a l y s i s ( F i g . 7) i n d i c a t e d j a c k k n i f e d c l a s s i f i c a t i o n p r o c e d u r e s c o r r e c t l y i d e n t i f i e d l a b o r a t o r y r e a r e d i n d i v i d u a l s t o t h e i r p o p u l a t i o n s w i t h 86 p e r c e n t a c c u r a c y . T h i s i s t h e same l e v e l of a c c u r a c y a s t h e w i l d s amples (93 p e r c e n t i n 1982 and 87 p e r c e n t i n 1983). A s i n g l e d i s c r i m i n a n t f u n c t i o n e x p l a i n e d 92 p e r c e n t of t h e t o t a l v a r i a t i o n i n m o r p h o l o g y i n t h e l a b o r a t o r y r e a r e d p o p u l a t i o n s ; d o r s a l f i n a r e a , c a u d a l p e d u n c l e l e n g t h , body d e p t h , head d e p t h and SNAPE were t h e c h a r a c t e r s c o n t r i b u t i n g most t o t h e d i s c r i m i n a t i o n . S i x t y - s i x (1982) and 44 (1983) p e r c e n t o f a l l p o s s i b l e c o m p a r i s o n s r e s u l t e d i n s i g n i f i c a n t d i f f e r e n c e s i n t h e w i l d s a m p l e s whereas 68 . p e r c e n t (31/45) r e s u l t e d i n s i g n i f i c a n c e i n t h e l a b o r a t o r y r e a r e d s a m p l e s . F o r t y - t w o p e r c e n t (19/45) o f t h e rank c o m p a r i s o n s were t h e same i n l a b o r a t o r y s a m p l e s as i n t h e 1982 w i l d s a m p l e s and 58 p e r c e n t were t h e same i n t h e l a b o r a t o r y s amples and i n t h e 1983 w i l d s a mples ( 3 4 / 4 5 ) , ( A p p e n d i x T a b l e A . 6 ) . C h a r a c t e r rank i n t h e l a b o r a t o r y samples was s i g n i f i c a n t l y c o r r e l a t e d w i t h c h a r a c t e r rank i n t h e 1983 w i l d s amples (Rs = 0.46, P < 0.05, df = 43) but not i n t h e 1982 w i l d s a m p l e s . The c h a r a c t e r s t h a t most c o n s i s t e n t l y r a n k e d t h e same i n l a b o r a t o r y and w i l d s a m p l e s were body d e p t h , p e d u n c l e d e p t h , head d e p t h , f i n e n e s s r a t i o and t h e mean o f body d e p t h and w i d t h (BWBD). The 1982 w i l d s a m p l e s and l a b o r a t o r y r e a r e d f i s h were a l s o s i m i l a r 35 F i g u r e 7. D i s c r i m i n a n t f u n c t i o n a n a l y s i s d e s c r i b i n g m o r p h o l o g i c a l v a r i a t i o n among t h e l a b o r a t o r y r e a r e d j u v e n i l e c oho salmon from t h e t h r e e s t u d y p o p u l a t i o n s . N u merals i n d i c a t e p o s i t i o n o f p o p u l a t i o n c e n t r o i d s ( +. 95 % c o n f i d e n c e l i m i t s ) , 1 = C o l d w a t e r R., 2 = M o r r i s o n C r . , 3 = Wade C r . E q u a t i o n s 13 and 14 a r e s t a n d a r d i z e d d i s c r i m i n a n t f u n c t i o n s , R1* i s p r o p o r t i o n of t o t a l v a r i a n c e a c c o u n t e d f o r by i n t e r p o p u l a t i o n d i f f e r e n c e s . The p e r c e n t a g e v a r i a n c e a l o n g e a c h a x i s i s t h e p e r c e n t a g e o f t h e e x p l a i n e d v a r i a n c e a c c o u n t e d f o r by e a c h a x i s . (13) DF 1.85 P e d l - 1.56 Bodyd - 13.23 DFA - 0.38 SNAPE + 0.81 HD + 12.10 = 0.74 (14) DF 2.92 HD - 0.63 Bodyd - 2.01 P e d l + 2.11 DFA - 1.04 SNAPE + 26.52 R1" = 0.20 3 t 37 i n p a i r e d f i n l e n g t h s and t h e 1983 w i l d sample a g r e e d w i t h t h e l a b o r a t o r y samples i n median f i n a r e a s , SNAP and SNAPE. The a n a l y s i s of w i l d samples from s u c e s s i v e y e a r s combined w i t h t h e b r e e d i n g e x p e r i m e n t s s u p p o r t t h e s u g g e s t i o n t h a t t h e m o r p h o l o g i c a l c h a r a c t e r i s t i c s o f t h e s t u d y p o p u l a t i o n s a r e l a r g e l y i n h e r i t e d . W i t h r e s p e c t t o t h e r e l a t i v e m a g n i t u d e o f i n d i v i d u a l t r a i t s , agreement between 1983 w i l d and l a b o r a t o r y r e a r e d s a m p l e s was h i g h , but agreement between w i l d b r o o d y e a r s amples was low. T h i s s u g g e s t s t h a t some t r a i t s a r e under t i g h t g e n e t i c c o n t r o l whereas o t h e r t r a i t s a r e more l a b i l e . In a l l w i l d and l a b o r a t o r y c o m p a r i s o n s C o l d w a t e r R i v e r f i s h c o n s i s t e n t l y had l e s s r o b u s t b o d i e s t h a n e i t h e r of t h e c o a s t a l p o p u l a t i o n s . In a d d i t i o n , C o l d w a t e r f i s h a l s o had s m a l l e r f i n a r e a s i n b o t h t h e 1983 w i l d and l a b o r a t o r y samples t h a n e i t h e r of t h e c o a s t a l p o p u l a t i o n s . The c h a r a c t e r s t h a t b e s t d i f f e r e n t i a t e d t h e w i l d samples a l s o were b e s t a t d i f f e r e n t i a t i n g t h e l a b o r a t o r y r e a r e d p o p u l a t i o n s ( i . e . Bodyd, HD, median f i n a r e a s ) . M o r p h o l o g i c a l T r e n d s and Swimming P e r f o r m a n c e The t r e n d s i n d i c a t e d i n t h e c o a s t a l v s i n t e r i o r ANOVA and m u l t i v a r i a t e a n a l y s e s a r e a l s o a p p a r e n t i n t h e Spearman rank c o r r e l a t i o n c o e f f i c i e n t s ( T a b l e 5 ) . A l l median f i n a r e a s , body d e p t h and p e d u n c l e d e p t h were n e g a t i v e l y c o r r e l a t e d w i t h 38 T a b l e 5. Spearman rank c o r r e l a t i o n c o e f f i c i e n t s between t h e d i s t a n c e t o t h e s e a from t h e n a t a l s t r e a m and m o r p h o l o g i c a l c h a r a c t e r s . O n l y t h o s e c o e f f i c i e n t s s i g n i f i c a n t a t t h e 0.05 l e v e l a r e l i s t e d . R i v e r C h a r a c t e r i s t i c Body Measurement Rs (N=10, df=8) D i s t a n c e t o Sea Bodyd - 0.83 Pedd - 0.59 DFA - 0.71 AFA - 0.85 " " CFA - 0.59 TMFA - 0.72 BWBD - 0.63 " FR - 0.71 d i s t a n c e f r o m t h e upper l i m i t o f spawning t o t h e s e a . A g a i n t h e r e s u l t s i n d i c a t e t h a t i n t e r i o r coho t e n d t o be l e s s r o b u s t i n body form t h a n c o a s t a l c o h o . C o a s t a l c oho s t o c k s i n g e n e r a l have d e e p e r , w i d e r b o d i e s , d e e p e r p e d u n c l e s and g r e a t e r median f i n a r e a s t h a n i n t e r i o r c o h o . From t h e m o r p h o l o g i c a l t r e n d s e v i d e n t i n t h e above a n a l y s e s p r e d i c t i o n s can be made r e g a r d i n g body f o r m and swimming p e r f o r m a n c e i n c o a s t a l and i n t e r i o r coho p o p u l a t i o n s . The c o a s t a l s t o c k s , w i t h g r e a t e r l a t e r a l s u r f a c e a r e a s have a g r e a t e r p o t e n t i a l f o r r a p i d t h r u s t g e n e r a t i o n and t h u s may be c a p a b l e o f g r e a t e r " b u r s t " o r f a s t - s t a r t swimming p e r f o r m a n c e t h a n i n t e r i o r c o h o . On t h e o t h e r hand, i n t e r i o r coho w i t h l o w e r s u r f a c e a r e a s and more f u s i f o r m b o d i e s may be a d a p t e d f o r f r i c t i o n a l d r a g r e d u c t i o n . T h i s may c o n t r i b u t e t o g r e a t e r 39 s u s t a i n e d ( s t a m i n a ) swimming p e r f o r m a n c e t h a n c o a s t a l coho and i s p e r h a p s c o n c u r r e n t w i t h t h e l o n g e r seaward and spawning m i g r a t i o n s o f i n t e r i o r c o h o . F o r t h e t h r e e coho p o p u l a t i o n s s t u d i e d i n d e t a i l a summary of p r e d i c t i o n s b a s e d on body form r e l a t i v e t o swimming p e r f o r m a n c e i s g i v e n i n T a b l e 6. E a c h o f T a b l e 6. Rank b a s e d on t h e d e g r e e of d e v e l o p m e n t of t h e f e a t u r e s c o n s i d e r e d most i m p o r t a n t i n b u r s t swimming and f r i c t i o n a l d r a g r e d u c t i o n . A h i g h rank t o t a l i n d i c a t e s h i g h p r e d i c t e d b u r s t swimming p e r f o r m a n c e and low p r e d i c t e d s u s t a i n e d swimming. (WC = Wade C r . , MC = M o r r i s o n C r . , CWR = C o l d w a t e r R . ) . W i l d 1983 L a b 1983 C h a r a c t e r WC MC CWR WC MC CWR Bodyd 3 2 1 3 2 1 Pedd 2 3 1 3 2 1 DFA+AFA 3 2 1 3 2 1 CFA 3 2 1 3 2 1 T o t a l 11 9 4 12 8 4 f o u r s e l e c t e d c h a r a c t e r i s t i c s was g i v e n a rank a c c o r d i n g t o t h e d e v e l o p m e n t o f t h e c h a r a c t e r i n e a c h p o p u l a t i o n . The r a n k s were t h e n summed w i t h no i n i t i a l d i f f e r e n t i a l w e i g h t i n g of t h e c h a r a c t e r s . T h u s , w i t h r e s p e c t t o b u r s t swimming p e r f o r m a n c e , t h e t o t a l r a n k s of t h e 1983 w i l d and l a b o r a t o r y samples r a n k s p r e d i c t t h a t C o l d w a t e r R i v e r f i s h w i l l have t h e p o o r e s t b u r s t p e r f o r m a n c e o f t h e t h r e e p o p u l a t i o n s . W i t h r e s p e c t t o s u s t a i n e d swimming t h e same d a t a p r e d i c t 40 t h a t C o l d w a t e r R i v e r f i s h s h o u l d e x h i b i t g r e a t e r s u s t a i n e d swimming a b i l i t i e s t h a n e i t h e r Wade or M o r r i s o n C r e e k f i s h . In b o t h w i l d and l a b o r a t o r y samples t h e h i g h l y r o b u s t Wade C r e e k f i s h a r e p r e d i c t e d t o be t h e p o o r e s t s u s t a i n e d swimmers. A d u l t M o r p h o m e t r i e s D e s p i t e t h e s m a l l number of a d u l t s a n a l y s e d i t i s c l e a r t h a t t h e i n t e r p o p u l a t i o n t r e n d s e v i d e n t i n j u v e n i l e samples were m a i n t a i n e d i n a d u l t s . A d u l t s from t h e i n t e r i o r ( C o l d w a t e r R i v e r ) had s i g n i f i c a n t l y s h a l l o w e r , l e s s r o b u s t b o d i e s and s m a l l e r median f i n a r e a s , and a l s o were l e s s v a r i a b l e i n t h e s e c h a r a c t e r s t h a n M o r r i s o n C r e e k a d u l t s ( T a b l e 7 ) . Head l e n g t h was s i g n i f i c a n t l y d i f f e r e n t between s e x e s i n C o l d w a t e r R i v e r a d u l t s and t h u s t h i s c h a r a c t e r was not u s e d i n i n t e r p o p u l a t i o n c o m p a r i s o n s . 41 T a b l e 7. R e s u l t s o f m o r p h o m e t r i c a n a l y s i s of a d u l t coho from t h e C o l d w a t e r R i v e r and M o r r i s o n C r e e k . V a l u e s a r e g e o m e t r i c means ( + SD, cm) a d j u s t e d t o 46.5 cm. F i n a r e a s a r e i n s q . cm. Measurement C o l d w a t e r R. M o r r i s o n C r . F{1,19) P N 10 11 Bodyd 10. ,0 (0. .45) 1 1 . . 1 (0. .59) 13. ,02 < 0. ,005 Pedd 3. ,90 (0. .22) 4. .25 (0. ,19) 6. ,71 < 0. ,05 DFA 15. .7 (2. .05) 20. .2 (2. ,95) 8. .70 < 0. .01 AFA 16. .7 (1 . .84) 20. .4 (2. .84) 7, .91 < 0, .05 CFA 29. .4 (2. .69) 38. .6 (3. .36) 33, .80 < 0, .001 TMFA 61 . 8 (4. .72) 79. .2 (7. .12) 26, .90 < 0, .001 BWBD 7. .72 (0. .50) 8. .50 (0. .44) 1 1 , .51 < 0, .005 FR 6. . 1 5 (0. .23) 5, .49 (0. .28) 25, .55 < 0. .001 HD 8, .55 (0, .51 ) 8, .60 (0, .61 ) 0, .04 > 0, .05 PART 2: SWIMMING EXPERIMENTS G e n e r a l methods B o t h w i l d and l a b o r a t o r y r a i s e d j u v e n i l e s were u s e d i n b u r s t and s u s t a i n e d swimming t e s t s . They came from t h e same p o p u l a t i o n s a s t h e f i s h u s e d i n t h e m o r p h o m e t r i c a n a l y s i s , b u t , t h e w i l d f i s h were not c o l l e c t e d by e l e c t r o s h o c k i n g . I n s t e a d , b a i t e d minnow t r a p s and s e i n e s were u s e d t o c o l l e c t w i l d j u v e n i l e s f o r swimming t e s t s . The e x p e r i m e n t s i n v o l v e d w i l d and l a b o r a t o r y r a i s e d j u v e n i l e s f r o m t h e C o l d w a t e r R i v e r , M o r r i s o n C r e e k and Wade C r e e k . The methods of r e a r i n g and m a i n t e n a n c e were as o u t l i n e d a b o v e . A l l swimming e x p e r i m e n t s were c o n d u c t e d 42 a t t h e U.B.C. s o u t h campus f i s h e r i e s l a b o r a t o r y . To t e s t whether d i f f e r e n c e s i n f r y s i z e a t emergence i s p o t e n t i a l l y an i m p o r t a n t v a r i a b l e i n f l u e n c i n g b u r s t swimming p e r f o r m a n c e , and s u b s e q u e n t l y s u r v i v a l from p r e d a t i o n , Wade C r e e k and M o r r i s o n C r e e k f r y were t e s t e d f o r b o t h b u r s t swimming p e r f o r m a n c e and s u r v i v a l from p r e d a t i o n . The emerged f r y were o i n c u b a t e d a t 2.1 + 0.43 C. In a l l swimming t e s t s f i s h were d e p r i v e d o f f o o d f o r 24 h o u r s b e f o r e t h e t e s t . In b u r s t swimming t e s t s , mean and maximum v e l o c i t i e s a t t a i n e d p e r b u r s t were s e l e c t e d a s c r i t e r i a t o a s s e s s b u r s t swimming p e r f o r m a n c e i n c o h o . K i n e m a t i c ( i . e. t h e f o r m o f body and f i n movements) f e a t u r e s , however, a r e a l s o i m p o r t a n t components of b u r s t swimming p e r f o r m a n c e (Webb 1978a). Y e t , w h i l e t h e c r i t e r i a c h o s e n i n t h i s s t u d y a r e r e c o g n i z e d as p a r t o f a " f a m i l y " of c r i t e r i a i m p o r t a n t i n b u r s t swimming p e r f o r m a n c e d i s p l a c e m e n t o v e r t i m e i s c o n s i d e r e d t h e b e s t o v e r a l l measure of p e r f o r m a n c e (Webb 1978b). I n t e r p o p u l a t i o n B u r s t Swimming T e s t s In t h e b u r s t swimming t e s t s f i s h were s e l e c t e d t o r e f l e c t a range o f s t a n d a r d l e n g t h s from a p p r o x i m a t e l y 40 mm t o 70 mm. E x p e r i m e n t s were c o n d u c t e d i n a 2.4 m x 1.8 m x 0.25 m 43 f i b e r g l a s s t a n k , c o n t a i n e d w i t h i n a 2.4 m h i g h D e x i o n framework w h i c h s u p p o r t e d a l i g h t - p r o o f , b l a c k c l o t h s h r o u d . The bot t o m of t h e tank was p a i n t e d w h i t e t o p r o v i d e c o n t r a s t , f o r f i l m i n g p u r p o s e s , between t h e f i s h and t h e tank b o t t o m . A 1.0 m x 0.1 m x 0.12 m p l e x i g l a s s t u n n e l l e d from t h e l a r g e t a n k t o a s m a l l e r 1.0 m x 1.0 m x 0.1 m p l e x i g l a s s " c o r r a l " . The c o r r a l was e q u i p p e d w i t h m e s h - s c r e e n e d p o r t s t o a l l o w w a t e r exchange w i t h t h e l a r g e r main t a n k . F o r f i l m i n g p u r p o s e s , t h e t u n n e l and c o r r a l s e r v e d t o o r i e n t t h e t e s t f i s h i n t h e camera f i e l d . F i s h were i n d i v i d u a l l y d i p n e t t e d i n t o t h e t u n n e l and a l l o w e d , f o r 10 m i n u t e s , t o a c c l i m a t i z e t o t h e s u r r o u n d i n g s . A g a t e l o c a t e d h a l f w a y down t h e t u n n e l was opened and t h e f i s h a l l o w e d t o swim down t h e t u n n e l i n t o t h e c o r r a l . T h i s u s u a l l y o c c u r r e d w i t h i n 1 or 2 m i n u t e s . S t a i n l e s s s t e e l w i r e mesh e l e c t r o d e s were l o c a t e d a t t h e o p e n i n g of t h e t u n n e l . An e l e c t r i c a l s t i m u l u s (1.5 v/cm AC) c o u l d be d e l i v e r e d t o i n i t i a t e b u r s t swimming a c t i v i t y . Water t e m p e r a t u r e was m a i n t a i n e d a t 13.5 + 1.0 C and t h e w a t e r l e v e l a t 8.0 cm. B u r s t swimming s e q u e n c e s were r e c o r d e d w i t h a Lowcam I I ( R e d l a k e S e r i e s 51) h i g h s p e e d c i n e camera p o s i t i o n e d t o r e c o r d swimming b u r s t s i n t h e c o r r a l by way of a m i r r o r mounted a t 45 . To p r o v i d e a d e q u a t e e x p o s u r e d u r i n g f i l m i n g t h e tank was i l l u m i n a t e d by t h r e e banks of 40 w a t t , c o o l - w h i t e f l u o r e s c e n t l i g h t s and f o u r 150 watt f l o o d l i g h t s . The f i l m u s e d was Kodak 4-X, 16 mm r e v e r s a l f i l m (400 ASA) s h o t a t f 2 . 8 a t 100 fr a m e s p e r s e c o n d . The p r o c e s s e d f i l m was a n a l y s e d frame by frame on a 44 P h o t o g r a p h i c A n a l y s i s L t d . m o t i o n a n a l y z e r s y s t e m . F a s t - s t a r t or b u r s t swimming b e h a v i o u r i n f i s h e s c o n s i s t s of t h r e e k i n e m a t i c s t a g e s (Weihs 1973; B l a k e 1 9 8 3 c ) : (1) a " p r e p a r a t o r y " , f a s t body bend i n t o a "C" shape, (2) a p r o p u l s i v e s t a g e , i n v o l v i n g r a p i d r e c o i l o f t h e t a i l and where t h e body i s formed i n t o a "C" shape i n t h e o p p o s i t e d i r e c t i o n and (3) a " g l i d i n g " o r " r e p e a t b u r s t " s t a g e , t h a t i s h i g h l y v a r i a b l e w i t h r e s p e c t t o d u r a t i o n and f o r m . B e c a u s e s t a g e t h r e e i s v a r i a b l e and k i n e m a t i c s t a g e two i s t h e main p r o p u l s i v e s t a g e (Weihs 1973), t h e frame by frame a n a l y s i s was c o n f i n e d t o s t a g e s one and two. The end p o i n t o f a n a l y s i s was one frame p a s t t h e end of s t a g e two ( F i g . 8 ) . S p a t i a l d i s p l a c e m e n t o v e r t i m e was t a k e n d i r e c t l y f r o m t h e f i l m e d s e q u e n c e s . By e m p l o y i n g t h e f r a m i n g r a t e a s t h e t i m e v a r i a b l e , v e l o c i t y c a l c u l a t i o n s were t h e n made from t h e s e d a t a . V e l o c i t i e s f o r e a c h f i s h were c a l c u l a t e d a t 0.01 s e c o n d t i m e i n t e r v a l s . Mean v e l o c i t y p e r b u r s t was c a l c u l a t e d f o r ea c h f i s h f r o m t h e v e l o c i t i e s a t i n d i v i d u a l 0.01 s e c o n d t i m e i n t e r v a l s and t h e n p o o l e d by p o p u l a t i o n . Maximum v e l o c i t y a t t a i n e d p e r b u r s t f o r e a c h f i s h was c a l c u l a t e d and t h e n were p o o l e d by p o p u l a t i o n . At e a c h s t a n d a r d l e n g t h t h r e e f i s h were t e s t e d . T h e s e d a t a formed t h e b a s i s f o r mean and maximum v e l o c i t y v s . s t a n d a r d l e n g t h r e g r e s s i o n s (Webb and C o r o l l a 1981). 45 F i g u r e 8. P o r t i o n of f a s t - s t a r t r e s p o n s e a n a l y s e d i n b u r s t swimming e x p e r i m e n t s . I l l u s t r a t e d i s t r a c i n g of 75mm coho from t o p view o v e r s u c c e s s i v e f r a m e s . Head o f ar r o w r e p r e s e n t s a n t e r i o r end o f f i s h . % 6 3 47 Emergence S i z e - B u r s t P e r f o r m a n c e E x p e r i m e n t In t h i s e x p e r i m e n t t h e e f f e c t on b u r s t swimming p e r f o r m a n c e o f d i f f e r e n c e s i n s i z e a t emergence was examined i n newly emerged f r y from M o r r i s o n and Wade c r e e k s . T w e n t y - f o u r h o u r s a f t e r emergence a sample of s i x t y f r y was removed from e a c h p o p u l a t i o n and t r a n s p o r t e d t o h o l d i n g t a n k s i n t h e s o u t h campus l a b o r a t o r y . A f t e r a f u r t h e r 24 h o u r s , t h i r t y f r y from e a c h p o p u l a t i o n were t e s t e d f o r b u r s t swimming p e r f o r m a n c e . A t t h i s t i m e a l l f r y a p p e a r e d t o have a c h i e v e d n e u t r a l bouyany, swam a c t i v e l y i n midwater and showed no v i s i b l e s i g n s of a y o l k - s a c . A f t e r e a c h f i s h was t e s t e d i t was a n a e s t h e t i z e d and i t s s t a n d a r d l e n g t h r e c o r d e d . V e l o c i t y a t e a c h of f i v e 0.01 s e c o n d t i m e i n t e r v a l s ( z e r o t o 0.05 s e c o n d s ) was c a l c u l a t e d f o r e a c h f i s h . F o r e a c h p o p u l a t i o n t h e s e v e l o c i t i e s were p o o l e d and a p o p u l a t i o n mean was c a l c u l a t e d a t e a c h t i m e i n t e r v a l . In a d d i t i o n , f o r e a c h p o p u l a t i o n , t h e v e l o c i t i e s were p o o l e d o v e r 0.05 s e c o n d s and an o v e r a l l mean v e l o c i t y was c a l c u l a t e d f o r e a c h p o p u l a t i o n . Maximum v e l o c i t y i n e a c h p o p u l a t i o n was a c h e i v e d a t 0.05 s e c o n d s , t h u s t h e p o p u l a t i o n mean v e l o c i t y a t 0.05 s e c o n d s was u s e d a s a measure o f t h e maximum v e l o c i t y a t t a i n e d by e a c h p o p u l a t i o n . 48 P r e d a t i o n T e s t s P r e d a t i o n t e s t s were run t o d e t e r m i n e whether p r e d a t i o n on newly emerged coho f r y i s s i z e d e p e n d e n t and p e r h a p s r e l a t e d t o b u r s t swimming p e r f o r m a n c e . T h e s e t e s t s were run i n 940 l i t r e o v a l , f i b e r g l a s s t a n k s . E a c h tan k was s u p p l i e d w i t h a c o n t i n u o u s f l o w of d e c h l o r i n a t e d w a t e r . The p r e d a t o r s (139-155 mm SL) were coho f i n g e r l i n g s ( i . e . 1+ i n age) o b t a i n e d from a l o c a l h a t c h e r y . F o r e a c h r e p l i c a t e two p r e d a t o r s were u s e d . The p r e d a t o r s were n a i v e t o l i v e p r e y and were p l a c e d i n t h e e x p e r i m e n t a l t a n k s and d e p r i v e d o f f o o d f o r one week b e f o r e a t e s t . T w e n t y - f o u r h o u r s b e f o r e a t e s t t h e p r e y ( f r y from Wade and M o r r i s o n c r e e k s ) were a n a e s t h e s i z e d , m easured f o r s t a n d a r d l e n g t h and marked w i t h e i t h e r a r i g h t o r l e f t p e l v i c f i n c l i p . A l l f i s h u s e d i n t h e p r e d a t i o n t e s t s a p p e a r e d h e a l t h y . The p r e y , 15 from e a c h p o p u l a t i o n , were p l a c e d t o g e t h e r i n t h e e x p e r i m e n t a l t a n k s i n mesh e n c l o s u r e s . They were a l l o w e d 24 h o u r s t o r e c o v e r from a n a e s t h e s i a and h a n d l i n g , and t h e n t h e e n c l o s u r e s were opened and p r e y and p r e d a t o r s were a l l o w e d t o i n t e r a c t f o r 48 h o u r s . A f t e r 48 h o u r s t h e p r e d a t o r s and p r e y were removed and p r e s e r v e d i n 10 % b u f f e r e d f o r m a l i n . Two t e s t s , e a c h w i t h two e x p e r i m e n t a l and one c o n t r o l r e p l i c a t e , were c o n d u c t e d . T e m p e r a t u r e i n t h e t e s t t a n k s f l u c t u a t e d o d i u r n a l l y between 9 and 10 C. 49 S t a m i n a Swimming T e s t s S t a m i n a t e s t s were c o n d u c t e d i n a swim t e s t i n g a p p a r a t u s b e l o n g i n g t o t h e B r i t i s h C o l u m b i a R e s e a r c h C o u n c i l . I t s s t r u c t u r e and s p e c i f i c a t i o n s o f component p a r t s a r e d e s c r i b e d i n Howard (1973) and T s u y u k i and W i l l i s c r o f t ( 1 9 7 7 ) . The s y s t e m was m o d i f i e d s l i g h t l y by p l a c i n g two No. 20 mesh (0.9 x 0.9 mm), s t a i n l e s s s t e e l t u r b u l e n c e s c r e e n s , s e p a r a t e d by 4.0 cm, a t t h e u p s t r e a m end o f t h e t u n n e l s . T h i s m o d i f i c a t i o n was n e c e s s a r y t o p r e v e n t s t r o n g r o t a t i o n a l w a ter f l o w a t t h e head of e a c h t u n n e l . W i t h o u t t h i s m o d i f i c a t i o n t h e r e were a r e a s a t t h e head of e a c h t u n n e l where j u v e n i l e c oho e x p e r i e n c e d w ater v e l o c i t i e s c o n s i d e r a b l y l o w e r t h a n t h o s e i n t h e downstream a r e a s o f t h e t u n n e l s . When f r y r e a c h e d a s t a n d a r d l e n g t h of a p p r o x i m a t e l y 50 mm t h e y were t a k e n f o r t r a i n i n g and t e s t i n g . At t h i s p o i n t , a sample o f t h i r t y i n d i v i d u a l s f r o m a p o p u l a t i o n were p l a c e d i n 210 l i t r e o v a l t r a i n i n g t a n k s . F i s h were t r a i n e d f o r a p e r i o d o f two weeks t o swim a t 2.5 body l e n g t h s / s e c o n d . T h i s was n e c e s s a r y t o b r i n g a l l t e s t f i s h up t o some minimum l e v e l of p e r f o r m a n c e . D u r i n g t r a i n i n g f i s h were f e d t h r e e t i m e s p e r day. S t a m i n a swimming p e r f o r m a n c e was measured u s i n g t h e " f i x e d -v e l o c i t y " method. T h i s method measures t h e t i m e r e q u i r e d f o r f i s h t o f a t i g u e when swimming a t a f i x e d w a ter v e l o c i t y ( B r e t t 1967; B e a m i s h 1978). A f t e r t h e two week t r a i n i n g p e r i o d , t w e l v e f i s h f r o m e a c h p o p u l a t i o n were p l a c e d i n t h e s t a m i n a t u b e s and 50 a l l o w e d t o a c c l i m a t i z e t o t h e t u n n e l s f o r two h o u r s . At t h i s t i m e t h e water v e l o c i t y was m a i n t a i n e d a t t h e " t r a i n i n g v e l o c i t y " (2.5 body l e n g t h s / s e c o n d ) . To e n c o u r a g e swimming i n t h e t e s t f i s h d u r i n g t h e a c c l i m a t i z a t i o n p e r i o d a downstream e l e c t r i c f i e l d (5.0 AC v o l t s ) was t u r n e d on. A f t e r two h o u r s t h e water v e l o c i t y i n t h e t u n n e l s was e l e v a t e d , o v e r a one m i n u t e p e r i o d , t o o n e - h a l f t h e t e s t v e l o c i t y and t h e n l e f t f o r 30 m i n u t e s . A f t e r 30 m i n u t e s , t h e water v e l o c i t y was e l e v a t e d t o t h e t e s t v e l o c i t y ( h e r e a f t e r r e f e r r e d t o as V t ) and t h e t i m e was r e c o r d e d ( a s To or t i m e z e r o ) . P i l o t e x p e r i m e n t s had i n d i c a t e d t h a t a t e s t v e l o c i t y of 7.0 body l e n g t h s / s e c o n d was needed t o i n d u c e f a t i g u e i n a l l p o p u l a t i o n s . As t h e t e s t p r o c e e d e d and f i s h f a t i g u e d t h e t i m e e a c h i n d i v i d u a l f a t i g u e d was n o t e d and t h e f a t i g u e d f i s h removed and t h e i r s t a n d a r d l e n g t h s r e c o r d e d . In o r d e r t o r e d u c e t h e i n h e r e n t i n t r a p o p u l a t i o n v a r i a b i l i t y i n swimming p e r f o r m a n c e and t o t e s t t h e " b e s t " i n d i v i d u a l s of e a c h p o p u l a t i o n o n l y t h o s e i n d i v i d u a l s t h a t c o u l d m a i n t a i n p o s i t i o n f o r a t l e a s t one m i n u t e a t V t were i n c l u d e d i n t h e a n a l y s i s . Two p o p u l a t i o n s were t e s t e d a t a t i m e , e a c h p o p u l a t i o n i n a s e p a r a t e t u n n e l . Over t h e r e p l i c a t e s e a c h p o p u l a t i o n was t e s t e d i n a l l t u n n e l s . The t u n n e l s were c o v e r e d w i t h b l a c k p o l y e t h e l y n e d u r i n g t e s t s . Swimming f i s h were p e r i o d i c a l l y c h e c k e d i n t h e t u n n e l s by l o o k i n g i n t o a m i r r o r p o s i t i o n e d a t 45 a l o n g t h e s i d e of e a c h t u n n e l . The water t e m p e r a t u r e i n t h e t u n n e l s was c o n t r o l l e d a t o 11.5 + 1.0 C. Water v e l o c i t i e s were measured w i t h an O t t 51 c u r r e n t m e t e r . D i s s o l v e d oxygen was m o n i t o r e d p e r i o d i c a l l y u s i n g a Y e l l o w S p r i n g s Co. D. 0. meter and i n a l l c a s e s d i s s o l v e d oxygen r e m a i n e d a t > 95 p e r c e n t s a t u r a t i o n t h r o u g h o u t t h e t e s t s . E a c h t e s t l a s t e d a minimum o f 360 m i n u t e s ( s e e B r e t t 1983) o r u n t i l a t l e a s t 50 p e r c e n t o f t h e i n d i v i d u a l s f a t i g u e d . A l l t e s t s were c o n d u c t e d i n Ju n e , J u l y and A u g u s t of 1983. S t a t i s t i c a l Methods In t h e p o p u l a t i o n b u r s t e x p e r i m e n t s , r e g r e s s i o n s were c a l c u l a t e d between b o t h maximum and mean v e l o c i t y p e r b u r s t and s t a n d a r d l e n g t h . D i f f e r e n c e s i n s l o p e s between g r o u p s were t e s t e d u s i n g a n a l y s i s o f c o v a r i a n c e ( S o k a l and R o h l f . 1 9 6 9 ) . B o t h mean and maximum v e l o c i t i e s a t t a i n e d by i n d i v i d u a l s i n e a c h p o p u l a t i o n were s t a n d a r d i z e d t o a common s t a n d a r d l e n g t h and were compared by ANCOVA. In t h e s i z e a t emergence e x p e r i m e n t , d i f f e r e n c e s i n egg volume, f r y l e n g t h a t emergence and b u r s t v e l o c i t i e s a t s p e c i f i c t i m e i n t e r v a l s were t e s t e d by a n a l y s i s of v a r i a n c e . Homogeneity of v a r i a n c e s was t e s t e d by B a r t l e t t ' s t e s t . R e s u l t s of t h e p r e d a t i o n e x p e r i m e n t s were a n a l y s e d by F i s h e r ' s E x a c t T e s t w i t h i n r e p l i c a t e s ( S t e e l and T o r r i e 1980); h e t e r o g e n e i t y t e s t s e m p l o y i n g t h e G - s t a t i s t i c were p e r f o r m e d t o v a l i d a t e p o o l i n g the r e s u l t s o f i n d i v i d u a l r e p l i c a t e s ( S n e d e c o r and C o c h r a n 1967). The G - s t a t i s t i c was t h e n c a l c u l a t e d f o r t h e p o o l e d r e s u l t s i n 52 t h e form o f a 2 X 2 c o n t i n g e n c y t a b l e ( S o k a l and R o h l f 1969). In t h e s t a m i n a e x p e r i m e n t s , r e g r e s s i o n s were c a l c u l a t e d between p r o b i t s of c u m u l a t i v e p e r c e n t f a t i g u e d and t h e l o g a r i t h m s ( b a s e i o ) o f i n d i v i d u a l f a t i g u e t i m e s ( F i n n e y 1971; T s u y u k i and W i l l i s c r o f t 1977). P r e l i m i n a r y e s t i m a t e s of p o p u l a t i o n mean f a t i g u e t i m e s and t h e d i s t r i b u t i o n a l s t a n d a r d d e v i a t i o n s r e s u l t i n g from t h i s a n a l y s i s ( B l i s s 1937) were u s e d t o c o m p l e t e f i n a l s o l u t i o n s f o r any t r u n c a t e d d i s t r i b u t i o n s ( B l i s s 1937; J o h n s o n and K o t z 1970). The a n t i l o g of t h e t i m e a t w h i c h 50 p e r c e n t of t e s t f i s h from a s i n g l e p o p u l a t i o n f a t i g u e d ( i . e. t h e FT50) was u s e d as an i n d e x o f swimming s t a m i n a ( B r e t t 1967). To t e s t f o r s t a t i s t i c a l s i g n i f i c a n c e among sample F T 5 0 ' s , an o v e r a l l a p p r o x i m a t i o n of a s i n g l e c l a s s i f i c a t i o n ANOVA ( S o k a l and R o h l f 1969) was c a l c u l a t e d . The a p p r o x i m a t e F s t a t i s t i c ( F ' ) c a l c u l a t i o n does n o t assume h o m o g e n e i t y o f sample v a r i a n c e s and t h e means a r e w e i g h t e d b a s e d on t h e r e c i p r o c a l of t h e v a r i a n c e of t h e sample from w h i c h e a c h mean was d e r i v e d . S i m i l a r i l y , p a i r w i s e a p p r o x i m a t e t - t e s t s ( S o k a l and R o h l f 1969) were u s e d t o t e s t f o r d i f f e r e n c e s between sample F T 5 0 ' s . To see i f m o r p h o l o g y was r e l a t e d t o swimming p e r f o r m a n c e s t a m i n a r a n k i n g was compared t o m o r p h o l o g y r a n k i n g , by c a l c u l a t i n g Spearman ra n k c o r r e l a t i o n c o e f f i c i e n t s . 53 Dead Drag D e t e r m i n a t i o n s The i n f l u e n c e of v a r i a t i o n i n body form on f r i c t i o n a l d r a g i n t h e t e s t p o p u l a t i o n s was i n v e s t i g a t e d by " d r o p - t a n k " e x p e r i m e n t s ( B l a k e 1979, 1983b). The d r o p t a n k c o n s i s t e d o f a 1.0 m x 0.12 m x 0.10 m p l e x i g l a s s tank ( F i g . 9 ) . The tank was e q u i p p e d w i t h l i g h t s o u r c e s and p h o t o s e n s o r c e l l s a t i t s upper and l o w e r e n d s . The p h o t o c e l l s were c o n n e c t e d t o a H e w l e t t -P a c k e r t 5327A t i m i n g - c o u n t i n g d e v i c e w i t h a maximum r e s o l u t i o n of ^ .0 ps. The f i s h t e s t e d were p r e s e r v e d s p e c i m e n s f r o m c o a s t a l (Wade C r e e k ) and i n t e r i o r ( C o l d w a t e r R i v e r ) p o p u l a t i o n s . F i v e d i f f e r e n t s i z e d f i s h f r o m e a c h p o p u l a t i o n were t e s t e d i n t h e f o l l o w i n g manner. The p a i r e d f i n s were removed f r o m e a c h f i s h and t h e f i s h were t h e n f r o z e n o v e r n i g h t i n a " s t r a i g h t -s t r e t c h e d " p o s i t i o n . I n d i v i d u a l d e n s i t i e s between s i z e - p a i r e d f i s h were s t a n d a r d i z e d , when a p p r o p r i a t e , by p l a c i n g s m a l l l e a d w e i g h t s i n t h e i r mouths. F i s h were h e l d w i t h a l l i g a t o r c l i p s f a s t e n e d t o a d a r t f l i g h t i n a v e r t i c a l , h e a d - f i r s t p o s i t i o n i n th e d r o p t a n k . The c a u d a l f i n was j u s t below t h e wa t e r s u r f a c e . To m i n i m i z e s i d e f l u t t e r a s t h e f i s h f e l l t h r o u g h t h e water column t h e d a r t f l i g h t a p p a r a t u s s l i d a l o n g a t a u t , s t a i n l e s s s t e e l w i r e . As a f i s h was r e l e a s e d i t b r o k e t h e i n i t i a l p h o t o c e l l beam and t h i s a c t i v a t e d t h e t i m e r . The t i m e r was s t o p p e d when t h e f i s h f e l l t h r o u g h t h e s e c o n d beam a t t h e b o t t o m 54 F i g u r e 9. D r o p t a n k a p p a r a t u s u s e d i n f r i c t i o n a l d r a g c o e f f i c i e n t e x p e r i m e n t . 55 56 of t h e t a n k . Time and d i s t a n c e measures were u s e d t o c a l c u l a t e t e r m i n a l v e l o c i t y . E x p e r i m e n t a l minimum d r a g c o e f f i c i e n t s a c t i n g on t h e d a r t f l i g h t , w i t h and w i t h o u t t h e f i s h a t t a c h e d , were c a l c u l a t e d from t h e f o l l o w i n g e q u a t i o n ( B l a k e 1979): C A = 1 . 3 3 * ^ ° ' * (2) were = d r a g c o e f f i c i e n t , = R e y n o l d s number. The R e y n o l d s numbers were c a l c u l a t e d f r o m : R b = LV/Y , (3) were L = s t a n d a r d l e n g t h , V = v e l o c i t y and Y = k i n e m a t i c v i s c o s i t y of water ( B l a k e 1979). E s t i m a t e s o f C«l f o r e a c h f i s h were c o r r e c t e d f o r t h e d r a g e f f e c t s of t h e d a r t f l i g h t a p p a r a t u s and were t h e n u s e d t o c a l c u l a t e f r i c t i o n a l d r a g (D^ ) o v e r a r a n g e o f v e l o c i t i e s ( B l a k e 1983d): Dj- = 0.5{y>(V) V * S^C^} (4) were f = d e n s i t y of water and S w = t o t a l w e t t e d s u r f a c e a r e a . In t h i s manner, t h e d i f f e r e n t i a l f r i c t i o n a l d r a g e f f e c t s e x p e r i e n c e d by d i f f e r e n t "morphs" c o u l d be d e t e r m i n e d . E a c h f i s h was t e s t e d t h i r t y t i m e s and d i f f e r e n c e s between e x p e r i m e n t a l l y d e t e r m i n e d d r a g c o e f f i c i e n t s and c a l c u l a t e d f r i c t i o n a l d r a g v a l u e s a t s e l e c t e d swimming v e l o c i t i e s were t e s t e d by ANOVA. The e s t i m a t i o n of d r a g c o e f f i c i e n t s by d r o p 57 t a n k e x p e r i m e n t s on p r e s e r v e d s p e c i m e n s of f i s h e s s u c h as s a l m o n i d s t h a t swim i n a u n d u l a t o r y , s u b - c a r a n g i f o r m mode, a r e p r o b a b l y l o w e r t h a n a c t u a l d r a g v a l u e s e x p e r i e n c e d by swimming f i s h . T h i s i s p r i m a r i l y due t o t h e n o n - u n d u l a t o r y m o t i o n of " f r e e f a l l i n g " p r e s e r v e d s p e c i m e n s u s e d i n d r o p tank e x p e r i m e n t s ( B l a k e 1983b). The d r o p t a n k e x p e r i m e n t s , however, do p r o v i d e r e l a t i v e d i f f e r e n c e s i n f r i c t i o n a l d r a g v a l u e s between d i f f e r e n t body f o r m s . In a d d i t i o n , c a n be e x p e c t e d t o be t h e p r o d u c t of t h e many components o f swimming d r a g ( i . e. f r i c t i o n a l d r a g , p r e s s u r e d r a g and i n t e r f e r e n c e d r a g ) however under t h e c o n d i t i o n s i n w h i c h s a l m o n i d s swim f r i c t i o n a l d r a g may be c o n s i d e r e d t h e major d r a g component ( s e e D i s c u s s i o n ) . R e s u l t s B u r s t Swimming E x p e r i m e n t s P o p u l a t i o n B u r s t Swimming A summary of s t a t i s t i c s f o r t h e r e g r e s s i o n s of maximum and mean v e l o c i t y p e r b u r s t a g a i n s t s t a n d a r d l e n g t h f o r t h e t h r e e s t u d y p o p u l a t i o n s i s p r e s e n t e d i n T a b l e s 8 and 9. A l t h o u g h a l l r e g r e s s i o n s were s i g n i f i c a n t , o n l y 65 p e r c e n t o f t h e v a r i a t i o n i n b o t h mean and maximum v e l o c i t y was e x p l a i n e d by t h e r e g r e s s i o n s . The r e l a t i v e l y s m a l l r a n g e of l e n g t h s and ^ 8 8. R e g r e s s i o n a n a l y s i s of mean v e l o c i t y (cm/s) p e r b u r s t s e q u e n c e on s t a n d a r d l e n g t h (mm) f o r w i l d a n d l a b o r a t o r y r e a r e d j u v e n i l e c oho from t h e t h r e e s t u d y p o p u l a t i o n s . The i n d i c a t e d p r o b a b i l i t y i s t h a t t h e s l o p e = 0 . P o p u l a t i o n x SL y - i n t e r c e p t s l o p e r 1 " N P W i l d Wade C r . M o r r i s o n C r . C o l d w a t e r R. 50. 11 52.23 53. 1 7 0.5004 0.3972 0.6817 0.7852 1.1120 0.501 5 .67 .70 .53 27 .003 28 .000 30 .007 Lab Wade C r . M o r r i s o n C r . C o l d w a t e r R. 52.52 52.72 52.75 0.6127 0.3862 0.7343 0.6951 1.0392 0.5930 .80 .76 .55 29 .000 30 .000 30 .009 T a b l e 9. R e g r e s s i o n a n a l y s i s o f maximum v e l o c i t y p e r b u r s t s e q u e n c e (cm/s) on s t a n d a r d l e n g t h (mm) f o r w i l d and l a b o r a t o r y r e a r e d j u v e n i l e c oho from t h e t h r e e s t u d y p o p u l a t i o n s . The i n d i c a t e d p r o b a b i l i t y i s t h a t t h e s l o p e = 0 . P o p u l a t i o n X SL y - i n t e r c e p t s l o p e r v N P W i l d Wade C r . 50, .31 0. 6480 0 .7962 .67 31 .003 M o r r i s o n C r . 53. .95 0. 7781 0 .7209 .65 26 .004 C o l d w a t e r R. 53. .09 0. 8234 0 .6978 .53 29 .008 Lab Wade C r . 53. .98 0. 7547 0 .9071 .63 28 .001 M o r r i s o n C r . 52. .70 0. 6461 0 .7183 .66 28 .001 C o l d w a t e r R. 52. .75 0. 81 04 0 .6576 .71 27 .000 60 i n d i v i d u a l v a r i a t i o n i n r e s p o n s e t o e l e c t r i c a l s t i m u l i p r o b a b l y c o n t r i b u t e d c o n s i d e r a b l e v a r i a t i o n t o p e r f o r m a n c e l e v e l s . A n a l y s i s o f c o v a r i a n c e ( T a b l e 10) i n d i c a t e s t h a t of t h e t w e l v e p o s s i b l e p a i r w i s e c o m p a r i s o n s between r e g r e s s i o n l i n e s t h e two s l o p e s were s i g n i f i c a n t l y d i f f e r e n t i n o n l y one c o m p a r i s o n . The r e g r e s s i o n of mean b u r s t v e l o c i t y on s t a n d a r d l e n g t h f o r t h e M o r r i s o n C r e e k w i l d sample had a s i g n i f i c a n t l y g r e a t e r s l o p e t h a n t h e same r e g r e s s i o n f o r t h e C o l d w a t e r R i v e r w i l d sample (ANCOVA, P < 0.05). C o a s t a l s a m p l e s p o s s e s s e d c o n s i s t e n t l y h i g h e r s l o p e s f o r t h e r e g r e s s i o n s o f b o t h mean and maximum v e l o c i t y p e r b u r s t on s t a n d a r d l e n g t h t h a n i n t e r i o r s a m p l e s . In c o n t r a s t , i n t e r i o r s amples p o s s e s s e d h i g h e r i n t e r c e p t s t h a n c o a s t a l samples and t h u s t h e r e was a l a r g e o v e r l a p i n a t t a i n e d v e l o c i t i e s o v e r t h e r a n g e o f s t a n d a r d l e n g t h s t e s t e d . Maximum v e l o c i t y - s t a n d a r d l e n g t h d a t a were p o o l e d i n t o " c o a s t a l " and " i n t e r i o r " g r o u p s and c o v a r i a n c e a n a l y s i s p e r f o r m e d on t h e p o o l e d d a t a . A l t h o u g h t h e s l o p e s were s t a t i s t i c a l l y e q u a l (ANCOVA, P > 0.05) and t h e maximum v e l o c i t i e s (Vmax) were s i m i l a r i n s m a l l f i s h , t h e y t e n d e d t o d i v e r g e a s l e n g t h i n c r e a s e d . Thus, t h e a d j u s t e d Vmax ( t o an o v e r a l l mean s t a n d a r d l e n g t h o f 54 mm) was h i g h e r i n t h e c o a s t a l sample t h a n i n t h e i n t e r i o r sample (102.3 cm/s v s 95.5 cm/ s) a l t h o u g h t h i s d i f f e r e n c e was n o t s i g n i f i c a n t (ANCOVA, P > 0.05). T h i s p r o g r e s s i v e d i v e r g e n c e between c o a s t a l and i n t e r i o r samples T a b l e 10. R e s u l t s of c o v a r i a n c e a n a l y s i s on mean b u r s t v e l o c i t y on s t a n d a r d l e n g t h and maximum b u r s t v e l o c i t y on s t a n d a r d l e n g t h f o r w i l d and l a b o r a t o r y r e a r e d j u v e n i l e c o h o from t h e t h r e e s t u d y p o p u l a t i o n s . WW = Wade w i l d , CL = C o l d w a t e r l a b , e t c . The i n d i c a t e d p r o b a b i l i t y i s t h a t t h e s l o p e s a r e common. T e s t S l o p e F - r a t i o P Vmean:WiId WW X MW WW X CW CW X MW 1.074 1 .401 4.8 0.3138 0.2512 0.0413* Vmean:Lab WL X ML WL X CL CL X ML 2.619 0.223 3.359 0.1212 0.6417 0.0810 Vmax:WiId WW X MW WW X CW CW X MW 0.728 1 .096 0.007 0.7873 0.7444 0.9364 Vmax:Lab WL X ML WL X CL CL X ML 0.514 1 .087 0.085 0.4815 0.3084 0.7742 62 of maximum v e l o c i t i e s a t t a i n e d a s s t a n d a r d l e n g t h i n c r e a s e d may r e s u l t f r o m an i n c r e a s i n g d i v e r g e n c e i n body m o r p h o l o g i e s as gr o w t h p r o c e e d s ( R i d d e l l e t a_l. 1981). The r o b u s t - b o d i e d c o a s t a l samples g e n e r a l l y a t t a i n e d h i g h e r Vmean and Vmax when a d j u s t e d t o o v e r a l l mean s t a n d a r d l e n g t h ( T a b l e 1 1 ) . The r a n k s o f a d j u s t e d v e l o c i t i e s a t t a i n e d were g e n e r a l l y i n t h e same o r d e r a s t h o s e b a s e d on m o r p h o l o g i c a l c o n s i d e r a t i o n s ( T a b l e 6 ) . The l a b o r a t o r y s a m p l e s p r o d u c e d t h e o n l y s t a t i s t i c a l l y s i g n i f i c a n t d i f f e r e n c e . The Wade C r e e k ( l a b ) mean a d j u s t e d Vmax was s i g n i f i c a n t l y g r e a t e r t h a n t h a t of C o l d w a t e r R i v e r (ANCOVA, P < 0.025). T a b l e 11. A d j u s t e d Vmean and Vmax a t t a i n e d d u r i n g b u r s t a c t i v i t y f o r w i l d ( a d j u s t e d t o 54 mm) and l a b o r a t o r y ( a d j u s t e d t o 55 mm) sam p l e s from t h e t h r e e s t u d y p o p u l a t i o n s . A l l v a l u e s a r e i n cm/s and a r e r e p o r t e d ± 1 SD. Sample s i z e s a r e as i n T a b l e s 8 and 9. Sample A d j u s t e d Vmean A d j u s t e d Vmax CWW 69.2 ± 6.07 102.3 ± 13.87 MW 71.8 ± 11.96 104.7 ±. 12.31 WW 74.1 + 7.28 104.7 + 11.18 CWL 58.8 + 7.77 9 0 . 7 + 1 0 . 5 1 ML 66.1 ± 9.26 97.9 + 13.45 WL 66.1 +. 5.03 102. 1 +_ 16.15 63 S i z e - a t - E m e r g e n c e M o r r i s o n C r e e k eggs were 61 p e r c e n t l a r g e r (F{1,58}=358, P < 0.001) and t h e newly emerged f r y 16 p e r c e n t l a r g e r (F{1,58}=629, P < 0.001) t h a n eggs and f r y from Wade C r e e k ( T a b l e 1 2 ) . The v e l o c i t y - t i m e r e l a t i o n s h i p s f o r t h e two p o p u l a t i o n s of f r y a r e shown i n F i g . 10, and t h e i r r e l a t i v e p e r f o r m a n c e s a t s e l e c t e d t i m e i n t e r v a l s a r e summarized i n T a b l e 13. A l t h o u g h t h e l a r g e r M o r r i s o n C r e e k f r y c o n s i s t e n t l y o u t p e r f o r m e d Wade C r e e k f r y , w i t h r e s p e c t t o mean v e l o c i t y o v e r t h e 0.1 s e c o n d t e s t t i m e (51.5 v s 48.4 cm/s, ANOVA P > 0.1) t h e d i f f e r e n c e was not s i g n i f i c a n t . However, a t e a c h 0.01 s e c o n d i n t e r v a l o v e r t h e f i r s t 0.05 s e c o n d s , t h e l a r g e r f r y a t t a i n e d an a v e r a g e 22 p e r c e n t h i g h e r v e l o c i t y , w i t h a peak of > 80 p e r c e n t h i g h e r v e l o c i t y a t 0.01 s e c o n d s . A v e r a g e d o v e r 0.05 s e c o n d s f o r a l l f r y , t h e l a r g e r M o r r i s o n C r e e k f r y a t t a i n e d s i g n i f i c a n t l y g r e a t e r mean v e l o c i t y t h a n t h e Wade C r e e k f r y (F{1,148} = 4.8, P < 0.05). F o r t h e l a r g e r f r y , maximum v e l o c i t y a t t a i n e d a l s o was g r e a t e r but was not s i g n i f i c a n t (F{1,148} = 1.36, P > 0 . 1 ) . At e a c h 0.01 s e c o n d t i m e i n t e r v a l t h e M o r r i s o n C r e e k emerged f r y a t t a i n e d s i g n i f i c a n t l y g r e a t e r v e l o c i t y t h a n d i d s m a l l e r Wade Cr e e k f r y (ANOVA, minimum F{1,58}= 4.2, P < 0.05) o v e r t h e f i r s t 0.03 s e c o n d s . T h e s e v e l o c i t y d i f f e r e n c e s were m a i n t a i n e d up t o 0.1 s e c o n d but were n o t s t a t i s t i c a l l y s i g n i f i c a n t . 12 Female standard l e n g t h , egg volume and emerged f r y standard l e n g t h f o r Wade and M o r r i s o n Creek coho p o p u l a t i o n s . P o p u l a t i o n Female SL (cm) Egg Volume (ml) Emergent S i z e (mm) N Mean SD N Mean SD N Mean SD Wade C r . 2 48.50 (5.06) 30 0.142 (0.111) 30 27.30 (0.45) M o r r i s o n C r . 3 47.02 (3.03) 30 0.228 (0.158) 30 31.10 (0.71) g u r e 10. V e l o c i t y - t i m e r e l a t i o n s h i p s f o r Wade and M o r r i s o n C r e e k emerged f r y . E a c h p o i n t r e p r e s e n t s mean ( ± SD) v e l o c i t y of t h i r t y f r y , p o o l e d by p o p u l a t i o n . TIM E ( X 1 0 ~ 2 SECONDS) T a b l e 13. B u r s t swimming p e r f o r m a n c e summary o v e r 0.05 s e c o n d s f o r emerged c o h o f r y from Wade and M o r r i s o n C r e e k s . Mean SL Wade C r . = 27.26 + 0.47 SD, mm. Mean SL M o r r i s o n C r . = 31.06 ± 0.69 SD, mm. V e l o c i t y v a l u e s a r e means ( +. SD, c m / s ) . Time I n t e r v a l Mean V e l o c i t y Maximum V e l o c i t y P o p u l a t i o n 0.01 0.02 0.03 0 - 0.05 0 - 0.05" N 30 30 30 256 30 Wade C r . 10.4 (8.0) 31.6 ( 1 5 . 6) 49.3 ( 1 5 . 6) 42.1 (23 .2) 67.8 ( 1 6 . 4) M o r r i s o n C r . 18.8 (11.8) 41.6 (16. 4) 55.2 ( 1 0 . 4) 47.7 (21 .5) 73.3 ( 1 9 . 4) D i f f e r e n c e ( % ) +81 + 31 +21 + 13 +8 68 P r e d a t i o n E x p e r i m e n t s The r e s u l t s of t h e p r e d a t i o n e x p e r i m e n t s a r e summarized i n T a b l e 14. In e a c h of t h e f o u r e x p e r i m e n t a l r e p l i c a t e s , t h e l a r g e r M o r r i s o n C r e e k f r y s u r v i v e d b e t t e r t h a n t h e Wade C r e e k f r y , t h r e e of t h e f o u r t r i a l s r e s u l t i n g i n s i g n i f i c a n t d i f f e r e n c e s ( G s t a t and F i s h e r ' s E x a c t T e s t , minimum P < 0.02). When t h e r e s u l t s of t h e f o u r r e p l i c a t e s were p o o l e d s u r v i v a l o f M o r r i s o n C r e e k f r y was s i g n i f i c a n t l y g r e a t e r t h a n t h a t of t h e s m a l l e r Wade C r e e k f r y ( T a b l e 14, G s t a t P < 0.0001). In c o n t r a s t , t h e r e were no s i g n i f i c a n t d i f f e r e n c e s i n s u r v i v a l from p r e d a t i o n between f r y f r o m t h e two p o p u l a t i o n s i n s i z e s o r t e d c o n t r o l t e s t s ( T a b l e 1 4 ) . S t a m i n a Swimming E x p e r i m e n t s In b o t h w i l d and l a b o r a t o r y r e a r e d s a m p l e s , C o l d w a t e r R i v e r ( i n t e r i o r ) f i s h showed s u b s t a n t i a l l y g r e a t e r swimming s t a m i n a (FT50) t h a n e i t h e r o f t h e two c o a s t a l p o p u l a t i o n s ( T a b l e 15, 16). F o r t h e C o l d w a t e r f i s h t h e FT50 v a l u e s were a p p r o x i m a t e l y 3.5 t i m e s t h o s e f o r Wade C r e e k f i s h and o v e r 7 t i m e s t h o s e of M o r r i s o n C r e e k w i l d f i s h (F'{8,33}= 104, P < 0.001). In p a i r w i s e a n a l y s i s i n o n l y two c a s e s ( M o r r i s o n C r e e k , P < 0.01-P < 0.001) were t h e r e s i g n i f i c a n t d i f f e r e n c e s i n FT50 v a l u e s w i t h i n a p o p u l a t i o n . In c o n t r a s t a l l C o l d w a t e r R i v e r FT50 v a l u e s were s i g n i f i c a n t l y h i g h e r (minimum P < 0.01) t h a n t h o s e T a b l e 14. S u r v i v a l f r o m p r e d a t i o n by coho f i n g e r l i n g s , a nd s i g n i f i c a n c e o f d i f f e r e n c e s , o f newly-emerged f r y f r o m Wade and M o r r i s o n C r e e k s . N i , Nf d e n o t e i n i t i a l a nd f i n a l p r e y numbers, % S d e n o t e s p e r c e n t a g e s u r v i v a l . The F i s h e r p r o b a b i l i t y a p p l i e s t o i n d i v i d u a l r e p l i c a t e s o n l y , p o o l e d t e s t s p r o b a b i l i t i e s a r e t h o s e o f t h e C h i -s q u a r e . P o p u l a t i o n Mean SL. N i Nf %S G s t a t , F i s h e r P ( ± : SD, mm) Wade C r . 26 .31 (0.58) 15 5 33.3 M o r r , C r . 30 .54 (0.69) 1 5 1 1 73.3 4.96, P < 0.05 Wade C r . 26 .63 (0.52) 1 5 7 46.7 M o r r . C r . 31 .19 (0.87) 1 5 1 3 86.7 5.68, P < 0.02 Wade C r . 27 . 33 (0.45) 1 5 5 33. 3 M o r r . C r . 30 . 1 5 (0.71) : 1 5 9 60.0 2.17, P > 0.10 Wade C r . 27 . 12 (0.65) 1 5 6 40.0 M o r r . C r . 31 .38 (0.74) 1 5 1 2 80.0 5.17, P < 0.03 H e t e r o g e n e i t y G s t a t 2.13, P > 0.50 P o o l e d G s t a t • 16.85, P < 0.001 Wade C r . 30 .19 (0.93) 15 13 86.6 M o r r . C r . 29 .93 (1.13) 15 13 86.6 0.00, P > 0.70 Wade C r . 31 .40 (0.67) 1 5 12 80.0 M o r r . C r . 31 .7.4 (0.86) 15 1 1 73.3 0.18, P > 0.66 H e t e r o g e n e i t y Sum P o o l e d G s t a t 0.07, P = 0.50 0.11, P = 0.74 70 of M o r r i s o n and Wade C r e e k w i l d samples and a l l Wade Cree k sample FT50's were s i g n i f i c a n t l y g r e a t e r t h a n t h o s e f o r M o r r i s o n C r e e k (P r a n g e 0.01-0.001). In l a b o r a t o r y r e a r e d s a m p l e s , t h e FT50 v a l u e s f o r C o l d w a t e r f i s h a v e r a g e d 4.3 t i m e s t h o s e of Wade C r e e k f i s h and o v e r 8 t i m e s t h o s e of M o r r i s o n C r e e k samples (F'{8,35}= 407, P < 0.001). Among t h e l a b o r a t o r y samples t h e r e was a t l e a s t one s i g n i f i c a n t d i f f e r e n c e i n w i t h i n p o p u l a t i o n c o m p a r i s o n s (minimum P < 0.01) f o r a l l t h r e e p o p u l a t i o n s . C o l d w a t e r R i v e r samples a g a i n had s i g n i f i c a n t l y g r e a t e r FT50's t h a n d i d a l l Wade and M o r r i s o n C r e e k samples (minimum P < 0. 0 0 1 ) . Wade C r e e k sample FT50's were s i g n i f i c a n t l y g r e a t e r t h a n M o r r i s o n C r e e k FT50's i n s i x of n i n e p o s s i b l e c o m p a r i s o n s (minimum P < 0.001) w h i l e two c o m p a r i s o n s were n o t s i g n i f i c a n t and i n one c a s e M o r r i s o n C r e e k FT50 was s i g n i f i c a n t l y g r e a t e r t h a n t h a t f o r Wade C r e e k (16.6 vs 9.2 min., P < 0.01). Thus, s t a m i n a swimming p e r f o r m a n c e when r a n k e d i n o r d e r o f d e c r e a s i n g p e r f o r m a n c e were, f o r b o t h w i l d and l a b o r a t o r y r a i s e d s a m p l e s , C o l d w a t e r R i v e r > Wade C r e e k > M o r r i s o n C r e e k . The m o r p h o l o g i c a l r a n k i n g s f o r t h e s e p o p u l a t i o n s showed a t e n d e n c y t o be a s s o c i a t e d w i t h g r e a t e r s u s t a i n e d swimming p e r f o r m a n c e , 1. e. g r e a t e r s t r e a m l i n i n g was a s s o c i a t e d w i t h h i g h e r s u s t a i n e d swimming p e r f o r m a n c e , however, t h i s r e l a t i o n s h i p was not s i g n i f i c a n t (Rs = 0.52, P > 0.05, d f = 4 ) . In b o t h l a b o r a t o r y and w i l d s a m p l e s , as p r e d i c t e d , C o l d w a t e r f i s h had t h e h i g h e s t s t a m i n a r a n k i n g . Wade C r e e k f i s h , however, c o n s i s t e n t l y o u t p e r f o r m e d M o r r i s o n C r e e k f i s h , and t h i s r e s u l t i s o p p o s i t e t o t h a t p r e d i c t e d on t h e b a s i s o f m o r p h o l o g y . 7/ T a b l e 15. C o m p a r a t i v e s t a m i n a swimming p e r f o r m a n c e among w i l d r e a r e d j u v e n i l e c o h o f r o m t h e t h r e e s t u d y p o p u l a t i o n s . P a i r e d d a t a i n d i c a t e p a i r e d t e s t s . P o p u l a t i o n Mean SL ( ± SD, mm) N V e l o c i t y (cm/s) FT50 (± SD, min) Coldw R. 49. 18 (1 .34) 1 2 63.5 (14. 6) Wade C r . 50.70 (1 .22) 1 1 34. 3 28.3 ( 9 . 1 ) Coldw R. 49.55 (1 .62) 1.0 79.9 (36. 03) Morr C r . 50.34 (1 .66) 1 2 34. 7 9.2 (3 . 58) Wade C r . 51 .32 (1 .43) 1 2 29.4 (3. 82) Morr C r . 50.58 (1 .98) 1 2 35. 4 9.9 (4. 73) Coldw R. 50.50 (1 .61 ) 1 1 79.9 (11. 46) Morr C r . 52.21 (1 .32) 1 1 35. 7 16.7 ( 5 . 16) Wade C r . 50.81 (2 .18) 11 35. 5 33.4 ( 7 . 36) 72-T a b l e 16. C o m p a r a t i v e s t a m i n a swimming p e r f o r m a n c e among l a b o r a t o r y r e a r e d j u v e n i l e c o h o from t h e t h r e e s t u d y p o p u l a t i o n s . . P a i r e d d a t a i n d i c a t e p a i r e d t e s t s . P o p u l a t i o n Mean SL N V e l o c i t y FT 50 ( ± SD, mm) (cm/s) ( + SD, min) Coldw R. 51 .71 (2. 02) " 10 105.9 (10.4) Morr C r . 52.01 ( 1 . 70) 1 1 36. 1 9. 1 (4.6) Coldw R. 53.81 (2. 08) 10 80.5 (10.3) Wade C r . 53. 33 (1 . 36) 10 37. 1 28.5 (6.5) Wade C r . 51.80 (1 . 14) 10 28.8 (10.1) Morr C r . 51 .06 (1 . 27) 11 36. 1 8.9 (5.1 ) Coldw R. 52. 1 5 (2. 1 1 ) 11 104.2 (40.8) Wade C r . 53.72 (2. 21) 9 36.7 9.2 (3.8) Morr C r . 53.82 (2. 08) 1 1 37.5 16.6 (5.2) 73 Dead D r a g D e t e r m i n a t i o n s I n d i v i d u a l t e r m i n a l v e l o c i t y d e t e r m i n a t i o n s were on a v e r a g e w i t h i n 2 p e r c e n t o f t h e mean f o r e a c h s p e c i m e n t e s t e d and i n o n l y one c a s e d i d an i n d i v i d u a l measurement e x c e e d e d t h e mean by 3 p e r c e n t o r g r e a t e r . Mean p e r c e n t a g e d e v i a t i o n s f r o m t h e mean t e r m i n a l v e l o c i t y a t t a i n e d were not s i g n i f i c a n t l y d i f f e r e n t between t h e s i z e p a i r e d f i s h f r o m Wade C r e e k and C o l d w a t e r R i v e r (ANOVA, P > 0 . 1 ) . Wade C r e e k ( c o a s t a l ) f i s h p o s s e s s e d s u b s t a n t i a l l y h i g h e r d r a g c o e f f i c i e n t s t h a n d i d C o l d w a t e r R i v e r ( i n t e r i o r ) f i s h ( T a b l e 1 7 ) . O v e r a l e n g t h r a n g e o f 50-63 mm d r a g c o e f f i c i e n t s f r o m t h e d r o p t a n k e x p e r i m e n t s a v e r a g e d 76 p e r c e n t h i g h e r i n Wade C r e e k f i s h t h a n i n C o l d w a t e r R i v e r f i s h (minimum F{1,58} = 26.7, P < 0.001). When t h e s e d r a g c o e f f i c i e n t s a r e c o m b i n e d w i t h s u r f a c e a r e a d e t e r m i n a t i o n s t o c a l c u l a t e ( e q u a t i o n 4, p. 56) e s t i m a t e s o f t h e f r i c t i o n a l d r a g a c t i n g on swimming f i s h o v e r a r a n g e of v e l o c i t i e s u s e d i n t h e s t a m i n a e x p e r i m e n t s two f e a t u r e s become e v i d e n t ( F i g . 1 1 ) : (1) f r i c t i o n a l d r a g i n c r e a s e s a t a g r e a t e r r a t e a s v e l o c i t y i n c r e a s e s i n t h e c o a s t a l t h a n i n i n t e r i o r f i s h and (2) i n t e r i o r f i s h e x p e r i e n c e a minimum o f 40 p e r c e n t l e s s f r i c t i o n a l d r a g a t 30 c m / s e c o n d (6 b o d y l e n g t h s / s e c o n d f o r 50 mm f i s h ) t h a n a c o a s t a l f i s h o f t h e same l e n g t h . A l l Df 3 0 v a l u e s were s i g n i f i c a n t l y h i g h e r i n Wade C r e e k f i s h (minimum F{1,58} = 66.3, P < 0. 0 0 1 ) . 7? T a b l e 17. C o m p a r a t i v e v a l u e s of d r a g c o e f f i c i e n t s and c a l c u l a t e d f r i c t i o n a l d r a g a t a swimming v e l o c i t y o f 30 cm s f o r c o a s t a l and i n t e r i o r j u v e n i l e c o ho s p e c i m e n s . A l s o i n d i c a t e d a r e d e n s i t y ( g / m l ) , t o t a l w e t t e d s u r f a c e a r e a ( c m 1 ) , f i n e n e s s r a t i o a nd volume ( m l ) . P o p u l a t i o n (SL mm) D e n s i t y Mean C^ S^ FR V o l Mean Df (30) Wade (50) 1 .02 0. 000074 15. 24 4. 48 3. 0 0.5100 Coldw (50) 1 .08 0. 000041 1 1 . 91 5. 85 2. 1 0.2217 Wade (52) 0 .91 0. 000113 16. 1 6 4. 31 3. 6 0.8237 Coldw (52) 0 .89 0. 000065 13. 31 5. 88 2. 5 0.3879 Wade (61 ) 1 .01 0. 000063 21 . 07 4. 48 4. 9 0.5996 Coldw (61 ) 1 .02 0. 000041 19. 31 5. 37 4. 6 0.3562 Wade (61 ) 1 . 1 1 0. 000335 20. 38 4. 76 4. 1 2.4283 Coldw (61 ) 1 .05 0. 000251 18. 06 5. 67 3. 8 1 .7058 Wade (63) 0 .91 0. 00018 22. 61 4. 91 5. 0 1 .8633 Coldw (63) 0 .92 0. 00008 19. 03 5. 67 4. 0 0.6644 75 The r e s u l t s of t h e m o r p h o l o g i c a l , s t a m i n a swimming and d r a g i n v e s t i g a t i o n s c l e a r l y i n d i c a t e t h a t t h e more f u s i f o r m body shape o f i n t e r i o r p o p u l a t i o n s i s a s s o c i a t e d w i t h l o w e r f r i c t i o n a l d r a g and h i g h e r swimming s t a m i n a , whereas t h e more r o b u s t body form of t h e c o a s t a l p o p u l a t i o n s i s a s s o c i a t e d w i t h i n c r e a s e d f r i c t i o n a l d r a g and d e c r e a s e d s t a m i n a swimming p e r f o r m a n c e . 76 F i g u r e 11. F r i c t i o n a l d r a g f o r c e as a f u n c t i o n o f v e l o c i t y f o r j u v e n i l e c o h o . E a c h p o i n t r e p r e s e n t s mean ( +_ SD) c a l c u l a t i o n f r o m t h i r t y r e p l i c a t e d r a g c o e f f i c i e n t d e t e r m i n a t i o n s f o r two j u v e n i l e c o h o , e a c h 52mm ( S L ) . Wade C r . (•), C o l d w a t e r R. (•) . 78 DISCUSSION M o r p h o l o g i c a l V a r i a t i o n i n Coho Salmon A l t h o u g h t h e coho salmon p o p u l a t i o n s i n c l u d e d i n t h i s s t u d y a r e m o r p h o l o g i c a l l y h e t e r o g e n o u s , s i m i l a r l e v e l s o f i n t r a s p e c i f i c v a r i a t i o n a r e w e l l documented i n o t h e r f i s h e s ( e . g. summer f l o u n d e r , P a r a l i c t h y s d e n t a t u s ( W i l k e t a l . 1980), w a l l e y e , S t i z o s t e d i o n v i t r e u m ( C o l b y and Nepszy 1981)) and w i t h i n t h e S a l m o n i d a e ( l a k e w h i t e f i s h , C o r e g o n u s c l u p e i f o r m i s ( I h s s e n e t a l . 1981) and A t l a n t i c s almon, Salmo s a l a r ( R i d d e l l and L e g g e t t 1981; R i d d e l l e t a l . 1 9 8 1 ) ) . Most o f t h e s e s t u d i e s of i n t r a s p e c i f i c v a r i a t i o n were c o n d u c t e d f o r management r e l a t e d p o p u l a t i o n i d e n t i f i c a t i o n . R e l a t i v e l y few s t u d i e s have a t t e m p t e d t o examine t h e f u n c t i o n a l b a s i s of i n t r a s p e c i f i c m o r p h o l o g i c a l v a r i a t i o n , a l t h o u g h o t h e r a s p e c t s of p o p u l a t i o n v a r i a t i o n have been c o n s i d e r e d i n t h i s r e s p e c t , e. g. a l l o z y m e v a r i a t i o n ( N o r t h c o t e and K e l s o 1981) and b e h a v i o u r a l v a r i a t i o n (Rosenau 1984). In s o u t h c o a s t a l and c e n t r a l B r i t i s h C o l u m b i a j u v e n i l e coho salmon c a n be c h a r a c t e r i z e d m o r p h o l o g i c a l l y i n t o two m a j o r " t y p e s " : (1) a " c o a s t a l " t y p e , w i t h l a r g e median f i n s and deep, r o b u s t b o d i e s and (2) an " i n t e r i o r " t y p e , w i t h s m a l l median f i n s and more s t r e a m l i n e d b o d i e s . G e o g r a p h i c p o p u l a t i o n g r o u p s have been s u g g e s t e d f o r o t h e r f a m i l i e s ( M c A l l i s t e r and L i n d s e y 1959; W i l k e t a l . 1980), and w i t h i n t h e S a l m o n i d a e e l e c t r o p h o r e t i c a l l y 79 d e t e c t a b l e g e n e t i c v a r i a t i o n ( U t t e r e t a l . 1980; McGregor 1983) s c a l e m o r p h o l o g y ( B i l t o n 1971; M c B r i d e and M a r s h a l l 1983) and c o m b i n a t i o n s o f a l l o z y m e , m o r p h o l o g i c a l and l i f e h i s t o r y c h a r a c t e r i s t i c s ( H j o r t and S c h r e c k 1982) have been u s e d t o d e f i n e g e o g r a p h i c f o r m s . In a s t u d y of g e n e t i c v a r i a t i o n i n p o p u l a t i o n s of r a i n b o w and s t e e l h e a d t r o u t , Salmo g a i r d n e r i , U t t e r and A l l e n d o r f (1977) s u g g e s t e d t h a t t h i s s p e c i e s , o v e r i t s e n t i r e n a t i v e r a n g e , c o n s i s t s of two major g r o u p s : a " c o a s t a l " g r o u p t h a t e x t e n d s from K o d i a k I s l a n d , A l a s k a s o u t h t o t h e Mad R i v e r of n o r t h e r n C a l i f o r n i a , and an " i n l a n d " g r o u p , t h a t r a n g e s e a s t o f t h e C a s c a d e M o u n t a i n s i n t h e F r a s e r and C o l u m b i a R i v e r s y s t e m s . T h i s " c o a s t a l - i n l a n d " c h a r a c t e r i z a t i o n o f S. q a i r d n e r i p o p u l a t i o n s i s a l s o e v i d e n t i n t h e i r m o r p h o l o g y ( i . e. s c a l e and p y l o r i c c a e c a c o u n t s and c o l o u r a t i o n G o l d 1977; Behnke 1981). P a r k i n s o n ( 1 9 8 0 ) , i n an a l l o z y m e s u r v e y o f B. C. s t e e l h e a d p o p u l a t i o n s , i d e n t i f i e d a c o a s t a l - i n t e r i o r d i s c o n t i n u i t y b a s e d on LDH and SOD l o c i w i t h i n t h e F r a s e r R i v e r s y s t e m . T h i s p a t t e r n was not p r e s e n t i n t h e more n o r t h e r l y Skeena and Dean R i v e r d r a i n a g e s ( s e e b e l o w ) . T h o r g a a r d ( 1 9 8 3 ) , however, a n a l y s e d chromosomal numbers and p a t t e r n i n r a i n b o w t r o u t and f a i l e d t o i d e n t i f y s u c h a p a t t e r n o v e r much of t h e same g e o g r a p h i c r a n g e . H j o r t and S c h r e c k (1982) s t u d i e d p h e n o t y p i c v a r i a t i o n i n j u v e n i l e coho from p o p u l a t i o n s i n W a s h i n g t o n , Oregon and C a l i f o r n i a . They a l s o r e p o r t e d g e o g r a p h i c p o p u l a t i o n g r o u p i n g s b a s e d on m o r p h o l o g i c a l , e l e c t r o p h o r e t i c and l i f e h i s t o r y 80 c h a r a c t e r i s t i c s . In Oregon, f o r i n s t a n c e , two d i s c r e t e c l u s t e r s were o b s e r v e d : p o p u l a t i o n s f r o m t h e n o r t h c o a s t and p o p u l a t i o n s f r o m t h e s o u t h c o a s t . U n f o r t u n a t e l y , none o f t h e i r p o p u l a t i o n s was from an i n t e r i o r s i t e . In t h e Yukon R i v e r , M c B r i d e and M a r s h a l l ( 1 9 8 3 ) , on t h e b a s i s of a d u l t s c a l e p a t t e r n , i d e n t i f i e d t h r e e b r o a d g e o g r a p h i c p o p u l a t i o n s of c h i n o o k salmon ( O n c o r h y n c h u s t s h a w y t s c h a ) : a l o w e r Yukon s t o c k f o u n d i n t r i b u t a r i e s from 0 t o 720 km u p s t r e a m , a m i d d l e Yukon s t o c k f o u n d i n t r i b u t a r i e s from 720 t o 1500 km u p s t r e a m and an upper Yukon s t o c k f o u n d i n t r i b u t a r i e s a t g r e a t e r t h a n 1500 km u p s t r e a m . U s i n g s c a l e p a t t e r n a n a l y s i s W i l c o c k and M c B r i d e (1983) were a b l e t o c o r r e c t l y c l a s s i f y 87 p e r c e n t of t h e a d u l t c h i n o o k salmon from t h e l o w e r Yukon R i v e r g i l l n e t f i s h e r i e s as e i t h e r o f l o w e r , m i d d l e o r upper r i v e r o r i g i n . Upper and m i d d l e Yukon c h i n o o k were most commonly c o n f u s e d w i t h e a c h o t h e r (16 and 31 p e r c e n t , r e s p e c t i v e l y ) whereas d i s c r i m i n a t i o n between upper and l o w e r Yukon c h i n o o k a v e r a g e d o v e r 90 p e r c e n t . In t h e p r e s e n t s t u d y a s i m i l a r p a t t e r n o f p o p u l a t i o n g r o u p i n g s and m i s c l a s s i f i c a t i o n was a p p a r e n t between c o a s t a l ( n o n - F r a s e r R i v e r d r a i n a g e ) , l o w e r F r a s e r and upper F r a s e r coho p o p u l a t i o n s . D i s c r i m i n a t i o n between i n t e r i o r and c o a s t a l p o p u l a t i o n s was o v e r 90 p e r c e n t and t h e most common m i s c l a s s i f i c a t i o n was between c o a s t a l and l o w e r F r a s e r p o p u l a t i o n s . Thus i n b o t h t h e Yukon and F r a s e r - S t r a i t of G e o r g i a c o m p a r i s o n s an i n t e r m e d i a t e g r o u p o c c u r s between two d i s t i n c t i v e p o p u l a t i o n s . In t h e Yukon i t i s t h e m i d d l e Yukon 81 g r o u p and i n t h e F r a s e r - S t r a i t of G e o r g i a c o m p a r i s o n i t i s t h e lo w e r F r a s e r g r o u p . In b o t h r i v e r s y s t e m s , however, a d i s t i n c t c o a s t a l - i n t e r i o r g r o u p i n g i s a p p a r e n t . In a d d i t i o n , t h e h i g h l e v e l of c o r r e c t c l a s s i f i c a t i o n , a s e i t h e r c o a s t a l o r i n t e r i o r b a s e d on t h e d i s c r i m i n a n t f u n c t i o n d e r i v e d i n t h i s s t u d y of j u v e n i l e c oho s p e c i m e n s from n o r t h - c o a s t a l B. C. , A l a s k a , and t h e upper C o l u m b i a R i v e r s y s t e m adds s u p p o r t t o t h e s u g g e s t i o n t h a t t h e c o a s t a l - i n t e r i o r d i s t i n c t i o n i n coho i s w i d e s p r e a d . M o r p h o l o g i c a l V a r i a t i o n and A d a p t a t i o n P h e n o t y p i c d i f f e r e n c e s among p o p u l a t i o n s a r e due t o g e n e t i c and e n v i r o n m e n t a l d i f f e r e n c e s ( R i c k e r 1972; Tave 1 9 8 4 ) . In an e l e c t r o p h o r e t i c s u r v e y o f west c o a s t s a l m o n i d s , U t t e r e t a_l . . (1980) s u g g e s t e d t h a t coho salmon may have e v o l v e d a genome " p o s s e s s i n g l i t t l e g e n e t i c v a r i a t i o n , b u t a h i g h l y a d a p t a b l e p h e n o t y p e " . The c o n s i s t e n t m o r p h o l o g i c a l d i s c r e t e n e s s o f w i l d samples ( i n t h r e e p o p u l a t i o n s s t u d i e d i n d e t a i l o v e r s u c c e s s i v e y e a r s ) , c o u p l e d w i t h t h e m a i n t e n a n c e of t h e i r m o r p h o l o g i c a l " c h a r a c t e r " when r e a r e d i n t h e l a b o r a t o r y , s t r o n g l y s u g g e s t s t h a t m o r p h o l o g i c a l d i f f e r e n c e s between coho p o p u l a t i o n s a r e , a t l e a s t p a r t i a l l y , g e n e t i c . G e n e t i c d i f f e r e n c e s between p o p u l a t i o n s i n morphology a r e w e l l known i n s a l m o n i d ( R i c k e r 1972; R i d d e l l e t e Q . 1981) and n o n - s a l m o n i d s p e c i e s ( B a r l o w 1961 ; Hagen 1973 ; M c P h a i l 1 9 8 4 ) . S i n c e t h e d e m o n s t r a t i o n of a g e n e t i c component i n p h e n o t y p i c v a r i a t i o n i s a major s t e p t o w a r d s e s t a b l i s h i n g t h a t s u c h v a r i a t i o n i s a d a p t i v e (Bock 82 1980), my d a t a s u g g e s t t h a t body form i n B. C. c oho p o p u l a t i o n s may be a d a p t i v e . I n t e r i o r p o p u l a t i o n s ( t h o s e u p s t r e a m o f H e l l ' s G a t e on t h e F r a s e r R i v e r ) must c o p e , b o t h as s m o l t s as a d u l t s , w i t h l o n g and d i f f i c u l t m i g r a t i o n s . The f r e s h w a t e r m i g r a t i o n s of i n t e r i o r p o p u l a t i o n s a r e p r o b a b l y e n e r g e t i c a l l y c o s t l y ( I d l e r and Clemens 1959; G i l h o u s e n 1980) and t h e r e f o r e s h o u l d s e l e c t f o r mechanisms t h a t m i n i m i z e e n e r g y e x p e n d i t u r e s . Thus, t h e d i s t i n c t i v e m o r p h o l o g y of i n t e r i o r p o p u l a t i o n s may c o n t r i b u t e t o t h e i r s u p e r i o r ( r e l a t i v e t o c o a s t a l p o p u l a t i o n s ) s u s t a i n e d swimming p e r f o r m a n c e . In t h e s e p o p u l a t i o n s j u v e n i l e body shape i s a t l e a s t p a r t i a l l y i n h e r i t e d and t h e i n t e r i o r body shape i s a s s o c i a t e d w i t h r e d u c e d f r i c t i o n a l d r a g and h i g h s u s t a i n e d swimming p e r f o r m a n c e . A l s o , among a d u l t s t h e r e i s t h e same g e n e r a l d i f f e r e n c e i n shape between i n t e r i o r and c o a s t a l f i s h . A l l o f t h i s s u g g e s t s t h a t body form i n j u v e n i l e c oho i s a d a p t i v e . In a d d i t i o n , t h e g e n e r a l l y h i g h e r l e v e l o f w i t h i n -g r o u p m o r p h o l o g i c a l v a r i a t i o n and g r e a t e r m o r p h o l o g i c a l o v e r l a p among c o a s t a l p o p u l a t i o n s ( r e l a t i v e t o i n t e r i o r p o p u l a t i o n s ) s u g g e s t s t h a t body form i s under more r i g o r o u s s e l e c t i o n i n i n t e r i o r p o p u l a t i o n s t h a n i n c o a s t a l p o p u l a t i o n s ( B a r l o w 1961). P e r h a p s t h e l o n g h i s t o r y of f a i l u r e i n a t t e m p t s t o r e h a b i l i t a t e upper F r a s e r R i v e r p o p u l a t i o n s of s o c k e y e salmon ( O n c o r h y n c h u s  n e r k a ) u s i n g l o w e r r i v e r " d o n o r " p o p u l a t i o n s ( W i t h l e r 1982) i s a r e s u l t o f s i m i l a r d i f f e r e n c e s i n c o a s t a l and i n t e r i o r s o c k e y e s a l m o n . R i c k e r (1972) s u g g e s t s t h a t t h e upper F r a s e r R i v e r 83 s o c k e y e p o p u l a t i o n s a r e " b e t t e r a d a p t e d t o t h e a r d u o u s j o u r n e y " t h a n l o w e r F r a s e r p o p u l a t i o n s . R i d d e l l and L e g g e t t (1981) a l s o f o u n d i n h e r i t e d body shape d i f f e r e n c e s i n Salmo s a l a r p a r r from a h i g h g r a d i e n t and h i g h - v e l o c i t y s y s t e m (Rocky Brook, New B r u n s w i c k ) and a low g r a d i e n t and low v e l o c i t y s y s t e m ( S a b b i e s R i v e r ) . The mouth of Rocky Brook i s , a l s o , o v e r t h r e e t i m e s f a r t h e r i n l a n d from t h e sea t h a n t h e mouth of S a b b i e s R i v e r . They s u g g e s t e d t h a t t h e d i f f e r e n c e s between t h e s e p o p u l a t i o n s i n p a i r e d f i n l e n g t h s were a r e s u l t o f d i r e c t i o n a l s e l e c t i o n t o h i g h e r a v e r a g e f l o w s i n Rocky B r o o k . They p o s t u l a t e d t h a t t h e l o n g e r p a i r e d f i n s of Rocky Brook p a r r i n c r e a s e d l i f t g e n e r a t i o n and t h u s r e d u c e t h e e n e r g y expended on m a i n t a i n i n g a f e e d i n g s t a t i o n i n r i f f l e i n h a b i t i n g Salmo s a l a r . They a l s o r e p o r t e d an a v e r a g e d i f f e r e n c e o f 5 p e r c e n t i n t h e f i n e n e s s r a t i o between t h e s e p o p u l a t i o n (Rocky Brook > S a b b i e s R i v e r ) , and c o n c l u d e d t h a t t h i s d i f f e r e n c e would r e s u l t i n o n l y s m a l l d i f f e r e n c e s i n p r e s s u r e d r a g between t h e s e p o p u l a t i o n s . P r e s s u r e d r a g , however, i s a n e g l i g i b l e f r a c t i o n o f t h e t o t a l d r a g f o r c e a c t i n g on f i s h when t h e y a r e swimming r o u g h l y p a r a l l e l t o t h e water f l o w (Webb 1975; B l a k e 1983d) and a t low R e y n o l d s numbers ( i . e. < 10r W a l t e r s 1961). F r i c t i o n a l d r a g i s t h e major d r a g component under t h e s e c o n d i t i o n s and a t low R e y n o l d s numbers ( i . e. f o r s a l m o n i d s a b o u t 10* ), and t h u s t h e r e l a t i v e m a g n i t u d e o f f r i c t i o n a l d r a g between f i s h o f d i f f e r e n t f i n e n e s s r a t i o s may be s i g n i f i c a n t i f t h e forms a r e o f d i f f e r e n t volumes 84 ( B l a k e 1983d). T y p i c a l l y , i n t e r i o r j u v e n i l e coho had l o w e r volumes ( i . e. l o w e r f i n a r e a s , l o w e r BWBD) and t h u s t h e i r h i g h e r f i n e n e s s r a t i o s may be u s e d as an i n d e x f o r r e l a t i v e d r a g p r e d i c t i o n s . The l o w e r volume p e r u n i t l e n g t h o f i n t e r i o r j u v e n i l e s p r o b a b l y c o n t r i b u t e s t o t h e i r l o w e r f r i c t i o n a l d r a g ( r e l a t i v e t o c o a s t a l j u v e n i l e s ) . T hus, t h e p a t t e r n of m o r p h o l o g i c a l v a r i a t i o n f o u n d i n Rocky Brook and S a b b i e s R i v e r salmon i s p a r a l l e l e d i n c o a s t a l and i n t e r i o r coho p o p u l a t i o n s . In b o t h c a s e s , t h e p o p u l a t i o n s t h a t i n h a b i t e d what may be h y d r o d y n a m i c a l l y more s e v e r e e n v i r o n m e n t s ( i . e. w ater v e l o c i t i e s and g r e a t e r d i s t a n c e i n l a n d ) were c h a r a c t e r i z e d by l o n g e r h e a d s , p a i r e d f i n l e n g t h s and g e n e r a l l y l e s s r o b u s t b o d i e s t h a n t h o s e p o p u l a t i o n s from l e s s s e v e r e r i v e r s y s t e m s . T h i s c o n v e r g e n c e s u g g e s t s t h a t some a s p e c t s o f s u c h h y d r o d y n a m i c e n v i r o n m e n t s a r e p o w e r f u l s e l e c t i v e f o r c e s . Coho j u v e n i l e s , however, t e n d t o l i v e i n m i c r o h a b i t a t s t h a t a r e g e n e r a l l y s l o w water a r e a s ( i . e. p o o l s , s i d e c h a n n e l s (Hartman 1965; S c o t t and Crossman 1 9 7 3 ) ) . Thus s e l e c t i o n f o r body form by w i t h i n - s t r e a m h y d r o d y n a m i c c o n d i t i o n s may n o t be as i n t e n s e i n j u v e n i l e coho as i n t h e r i f f l e i n h a b i t i n g S. s a l a r . t n a d d i t i o n , t h e m a i n t e n a n c e of t h e c o a s t a l - i n t e r i o r d i f f e r e n t i a t i o n i n a d u l t coho s u g g e s t s t h a t i n coho t h e o b s e r v e d body f o r m p a t t e r n may, i n p a r t , r e s u l t from s e l e c t i o n a s s o c i a t e d w i t h l o n g m i g r a t i o n s . Thus, i n t e r i o r p o p u l a t i o n s have l e s s r o b u s t b o d i e s and t h e r e f o r e e x p e r i e n c e l e s s f r i c t i o n a l d r a g t h a n c o a s t a l p o p u l a t i o n s . 85 E v i d e n c e from o t h e r s t u d i e s a l s o s u g g e s t s , i n d i r e c t l y , t h a t t h e i n t e r i o r coho body form may be an a d a p t i v e r e s p o n s e t o l o n g f r e s h w a t e r m i g r a t i o n s . The h i g h l e v e l of "homing" i n P a c i f i c s almon ( J o n e s 1962) s u g g e s t s t h a t l o c a l a d a p t a t i o n i s i m p o r t a n t i n t h e s u c c e s s f u l c o m p l e t i o n o f t h e i r l i f e h i s t o r y (Banks 1969; Bams 1976). The i n f l u e n c e of r i v e r h y d r o d y n a m i c s ( i . e. m i g r a t i o n d i s t a n c e , d i f f i c u l t y of w i t h i n s t r e a m m i g r a t i o n ) a s a s e l e c t i v e f o r c e has a l s o been s u g g e s t e d a s an e x p l a n a t i o n f o r t h e e v o l u t i o n of what a r e v i e w e d as a d a p t i v e l i f e h i s t o r y v a r i a t i o n s i n b o t h A t l a n t i c salmon ( S c h a f f e r and E l s o n 1975) and P a c i f i c s a l m o n i d s (Whelan e t a l . 1982; H e a l y 1983). F o r example, t h e p e r c e n t a g e of g r i l s e (one s e a - w i n t e r mature f i s h ) , age a t f i r s t spawning and mean sea age a r e c o r r e l a t e d w i t h r e l a t i v e d i f f i c u l t y of spawning m i g r a t i o n s i n A t l a n t i c salmon p o p u l a t i o n s . P o p u l a t i o n s w i t h d i f f i c u l t m i g r a t i o n s have a low e r p e r c e n t a g e of g r i l s e , a h i g h e r mean age a t f i r s t s p a w n i n g, and l o n g e r mean sea age t h a n p o p u l a t i o n s w i t h l e s s a r d u o u s m i g r a t i o n s ( S c h a f f e r and E l s o n 1975; Power 1981; T h o r p e and M i t c h e l l 1981). F u r t h e r , s t e e l h e a d t r o u t i n t h e upper F r a s e r R i v e r a r e c h a r a c t e r i z e d by g e n e r a l l y l a r g e r body s i z e , l o n g e r sea age and, p e r h a p s most i m p o r t a n t l y , l o w e r v a r i a n c e i n t h e s e c h a r a c t e r i s t i c s t h a n c o a s t a l p o p u l a t i o n s (E . P a r k i n s o n , p e r s . comm.). D i f f i c u l t y of f r e s h w a t e r m i g r a t i o n has a l s o been i m p l i c a t e d i n t h e e v o l u t i o n o f v a r i a t i o n i n l i f e h i s t o r y t r a i t s of o t h e r anadromous f i s h e s , ( e . g. A m e r i c a n shad, A l o s a s a p i d i s s i m a , G l e b e and L e g g e t t 1976). T h e s e examples a l l 86 s u p p o r t t h e c o n t e n t i o n t h a t d i f f i c u l t y of m i g r a t i o n i s a p o w e r f u l s e l e c t i v e f o r c e a c t i n g on anadromous s a l m o n i d s . The a d a p t i v e r e l a t i o n s h i p between body form and s u s t a i n e d swimming p e r f o r m a n c e s u g g e s t e d above i s l i m i t e d by two f a c t o r s . F i r s t , t h e r e a r e few d i r e c t s t u d i e s of t h e e f f e c t s of i n t r a s p e c i f i c n a t u r a l v a r i a t i o n i n body m o r p h o l o g y on s u s t a i n e d swimming p e r f o r m a n c e . Thus, t h e r e i s l i t t l e work w i t h w h i c h t o compare t h e r e s u l t s o f t h e p r e s e n t s t u d y . In a d d i t i o n , c o r r e l a t i o n o f t r a i t s w i t h f e a t u r e s of p e r f o r m a n c e , or e n v i r o n m e n t , i s an u n c e r t a i n method of i d e n t i f y i n g a d a p t a t i o n s . C o r r e l a t i o n d o e s not n e c e s s a r i l y i m p l y a c a u s e and e f f e c t . C o r r e l a t i o n , however, can p r o v i d e a f i r s t s t e p i n i d e n t i f y i n g f e a t u r e s a s a d a p t i v e . (Bock 1980). Some e v i d e n c e , however, does e x i s t f r o m o t h e r s p e c i e s t h a t s u p p o r t t h e h y p o t h e s i s t h a t r e d u c e d body r o b u s t n e s s i s an a d a p t a t i o n t h a t i n c r e a s e s s u s t a i n e d swimming p e r f o r m a n c e . F o r example, s t e e l h e a d from t h e Thompson R i v e r (an i n t e r i o r p o p u l a t i o n ) show r e d u c e d body r o b u s t n e s s r e l a t i v e t o c o a s t a l p o p u l a t i o n s ( E . P a r k i n s o n p e r s . comm.) and a s i m i l a r p a t t e r n of r e d u c e d body r o b u s t n e s s and i n c r e a s e d s u s t a i n e d swimming p e r f o r m a n c e i s documented i n s t r a i n s of d o m e s t i c a t e d r a i n b o w t r o u t (Thomas and Dohahoo 1977). Thomas and Dohahoo r e p o r t e d t h a t t h e New Z e a l a n d and Sand C r e e k (Wyoming) s t r a i n s of r a i n b o w t r o u t had s i g n i f i c a n t l y g r e a t e r s u s t a i n e d swimming p e r f o r m a n c e and were a l s o more " s t r e a m l i n e d " t h a n t h e " d e e p b o d i e d " M a n c h e s t e r (Iowa) s t r a i n . U n f o r t u n a t e l y , t h e i r s t u d y i s c o m p l i c a t e d s i n c e t h e two " s t r e a m l i n e d " s t r a i n s 87 have been d o m e s t i c a t e d f o r s h o r t e r p e r i o d s ( i . e. t h e y were d e s c r i b e d as " s e m i w i l d " ) t h a n t h e " d e e p b o d i e d " s t r a i n . The d i f f e r e n c e s i n s u s t a i n e d swimming p e r f o r m a n c e between t h e s e s t r a i n s may s i m p l y r e f l e c t w i l d v s d o m e s t i c d i f f e r e n c e s and n o t d i f f e r e n c e s i n body s h a p e . D e c r e a s e d body r o b u s t n e s s i s a u n i v e r s a l f e a t u r e of t h e p a r r - s m o l t t r a n s f o r m a t i o n i n anadromous s a l m o n i d s ( E v r o p e i t s e v a 1962; V a n s t o n e and M a r k e r t 1968; F e s s l e r and Wagner 1969). S i n c e i t i s t h e s m o l t s and o l d e r l i f e h i s t o r y s t a g e s t h a t m i g r a t e t h i s may be a f u r t h e r example o f body form a d a p t a t i o n ( t h r o u g h c h a n g e s i n a l l o m e t r i c growth) t o i n c r e a s e s u s t a i n e d swimming p e r f o r m a n c e . The c h a n g e s i n body form r e p o r t e d f o r s m o l t i n g A t l a n t i c salmon ( e . g. i n c r e a s e i n r e l a t i v e head l e n g t h , d e c r e a s e i n body d e p t h and p e d u n c l e d e p t h ) were r e v e r s e d i n s m o l t s h e l d i n f r e s h w a t e r a f t e r t h e n o r m a l s m o l t p e r i o d ( E v r o p e i t s e v a 1962; F e s s l e r and Wagner 1969), a g a i n t h i s s u g g e s t s t h a t t h e c h a n g e s a r e p r e p a r a t o r y f o r m i g r a t i o n and t h a t i f m i g r a t i o n does n o t o c c u r t h e y w i l l be r e v e r s e d . F i n a l l y , Y e v s i n (1976, 1977) r e p o r t e d t h a t i n r i v e r s o f t h e White Sea B a s i n b o t h summer and autumn se a t r o u t (Salmo t r u t t a ) a r e c h a r a c t e r i z e d by deep and s h a l l o w - b o d i e d f o r m s . Y e v s i n s u g g e s t e d t h a t t h e body form c h a r a c t e r i s t i c f o r a p o p u l a t i o n was r e l a t e d t o t h e n a t u r e of t h e spawning m i g r a t i o n ; t h o s e p o p u l a t i o n s w i t h l o n g and d i f f i c u l t m i g r a t i o n s were s h a l l o w -b o d i e d whereas t h o s e w i t h r e l a t i v e l y e a s i e r m i g r a t i o n s were d e e p - b o d i e d . Y e v s i n (1977) a l s o r e p o r t e d t h a t w i t h i n r i v e r s t h e 88 d i f f e r e n c e s i n body form between autumn and summer " r a c e s " of t h e sea t r o u t were o f t e n r e v e r s e d d e p e n d i n g on w h i c h r a c e e x p e r i e n c e d t h e most d i f f i c u l t m i g r a t i o n . In c o h o , t h e s u g g e s t i o n t h a t t h e i n t e r i o r body form i s an a d a p t i o n t o r e d u c e d r a g must be tempered by c o n s i d e r a t i o n o f f l o w r e g i m e s under n a t u r a l r i v e r c o n d i t i o n s . The e x p e r i m e n t a l l y d e t e r m i n e d d i f f e r e n c e s i n f r i c t i o n a l d r a g between t h e c o a s t a l and i n t e r i o r j u v e n i l e s a r e l i m i t e d i n t h e i r a p p l i c a t i o n t o anadromous f i s h . The c o m p a r i s o n s a r e r e l e v a n t o n l y under c o n d i t i o n s o f p r o l o n g e d swimming a t s t e a d y , u n i f o r m f l o w . Thus, a l t h o u g h d r a g d i f f e r e n c e s may be s i g n i f i c a n t under l a b o r a t o r y c o n d i t i o n s , f l o w i n n a t u r a l r i v e r s t h a t c o n f o r m t o t h e s e " i d e a l " c o n d i t i o n s a r e p r o b a b l y r a r e . I t i s more l i k e l y t h a t n a t u r a l r i v e r s a r e t u r b u l e n t and t h a t swimming b e h a v i o u r d u r i n g m i g r a t i o n i s o f t e n u n s t e a d y . D i r e c t e x p e r i m e n t a l s t u d i e s o f f i s h swimming p e r f o r m a n c e under s u c h c o n d i t i o n s , however, have no t been a t t e m p t e d ( see B l a k e I983e f o r a s h o r t r e v i e w ) . In a d d i t i o n , s t o c h a s t i c e v e n t s may i n f l u e n c e t h e s u c c e s s f u l p a s s a g e of i n d i v i d u a l f i s h a t p a r t i c u l a r i l y d i f f i c u l t m i g r a t i o n p o i n t s . Thus any f i r m c o n c l u s i o n s c o n c e r n i n g t h e r e l a t i v e r o l e o f body form i n m i g r a t i o n s u c e s s must a w a i t d e t a i l e d s t u d y of t h e b e h a v i o u r and p e r f o r m a n c e o f f i s h e s swimming u n d e r more n a t u r a l , e s p e c i a l l y t u r b u l e n t , f l o w c o n d i t i o n s . C o l d w a t e r R i v e r ( i n t e r i o r ) coho j u v e n i l e s had, on a v e r a g e , f o u r t o f i v e t i m e s t h e s u s t a i n e d swimming p e r f o r m a n c e o f c o a s t a l 89 j u v e n i l e s . S i n c e t h e s e r e l a t i v e d i f f e r e n c e s a r e m a i n t a i n e d i n j u v e n i l e s r e a r e d i n t h e l a b o r a t o r y from eggs t h e y a r e p r o b a b l y i n h e r i t e d . I n t e r p o p u l a t i o n d i f f e r e n c e s i n s u s t a i n e d swimming p e r f o r m a n c e i n " s m o l t " coho were a l s o d e m o n s t r a t e d by B e s n e r and S m i t h (1983) and a g a i n i t was s u g g e s t e d t h a t t h e s e d i f f e r e n c e s a r e g e n e t i c . In s t e e l h e a d T s u y u k i and W i l l i s c r o f t (1977) d e m o n s t r a t e d t h a t l a b o r a t o r y r e a r e d Thompson R i v e r ( u p p e r F r a s e r R i v e r ) j u v e n i l e s p o s s e s s e d s i g n i f i c a n t l y h i g h e r swimming s t a m i n a (FT50) t h a n j u v e n i l e s from t h e V e d d e r R i v e r ( l o w e r F r a s e r R i v e r ) . The h i g h e r s u s t a i n e d swimming p e r f o r m a n c e of t h e Thompson R i v e r s t e e l h e a d was c o r r e l a t e d w i t h h i g h e r l e v e l s of t h e LDH-A a l l e l e . T h i s a l l e l e h as been f u n c t i o n a l l y a s s o c i a t e d , t h r o u g h e l e v a t i o n o f m u s c u l a r f a t i g u e t h r e s h o l d s , w i t h i n c r e a s e d s u s t a i n e d swimming a b i l i t y ( T s u y u k i and W i l l i s c r o f t 1977). Thus, t h e i n c r e a s e d s u s t a i n e d swimming p e r f o r m a n c e of b o t h upper F r a s e r s t e e l h e a d and coho a p p e a r t o be a d a p t a t i o n s t o t h e r e l a t i v e l y l o n g and more d i f f i c u l t m i g r a t i o n r o u t e s t r a v e r s e d by t h e s e s t o c k s compared t o c o a s t a l s t o c k s . The c l e a r d i c h o t o m y i n s u s t a i n e d swimming p e r f o r m a n c e between c o a s t a l and i n t e r i o r p o p u l a t i o n s may be due t o s p e c i f i c v e l o c i t y b a r r i e r s e n c o u n t e r e d i n m i g r a t i o n ( e . g. H e l l ' s G a t e i n the F r a s e r Canyon, r a p i d s e c t i o n s of Thompson R i v e r ) r a t h e r t h a n t h e l e n g t h of m i g r a t i o n . S uch r e g i o n s have h i s t o r i c a l l y r e p r e s e n t e d s i g n i f i c a n t h y d r o d y n a m i c b a r r i e r s t o f i s h p a s s a g e ( R i c k e r 1950, 1972). The e n e r g y e x p e n d i t u r e s r e q u i r e d t o m i g r a t e t h r o u g h s u c h v e l o c i t y b a r r i e r s may have s e l e c t e d f o r 90 t r a i t s w h i c h i n c r e a s e m i g r a t i o n s u c c e s s . The s e l e c t i v e n a t u r e o f (1) d i s t a n c e and (2) r a p i d w ater may be i n t e n s i f i e d by t h e f a c t t h a t t h e u p s t r e a m m i g r a t i o n i s a spawning m i g r a t i o n . C e r t a i n l y , d e l a y s i n m i g r a t i o n or s i t u a t i o n s t h a t i n c r e a s e e n e r g y e x p e n d i t u r e on r o u t e a r e known t o r e d u c e spawning s u c c e s s ( R i c k e r 1950; I d l e r and Clemens 1959; Geen 1975). The r o l e of t h e F r a s e r Canyon as a s e l e c t i v e f o r c e a c t i n g t o i n c r e a s e s u s t a i n e d swimming p e r f o r m a n c e i s a l s o s u g g e s t e d i n t h e r e s u l t s of P a r k i n s o n ( 1 9 8 0 ) . P a r k i n s o n f o u n d a s h a r p d i s c o n t i n u i t y i n t h e a l l e l e s p r e s e n t a t LDH l o c u s between t h e upper and l o w e r F r a s e r s t e e l h e a d p o p u l a t i o n s . An e q u i v a l e n t d i c h o t o m y , however, was not p r e s e n t i n upper Dean o r upper Skeena r i v e r s . P e r h a p s t h e s e s y s t e m s l a c k f a s t - w a t e r s e c t i o n s o f t h e m a g n i t u d e of t h e F r a s e r Canyon and s e l e c t i o n f o r i n c r e a s e d s u s t a i n e d swimming p e r f o r m a n c e i s not as s t r o n g a s i n t h e F r a s e r s y s t e m . Thus, t h e LDH-A a l l e l e , t h a t i s common t o b o t h t h e upper F r a s e r and upper C o l u m b i a s t e e l h e a d p o p u l a t i o n s , may be a s s o c i a t e d w i t h s e l e c t i o n f o r i n c r e a s e d s u s t a i n e d swimming p e r f o r m a n c e . A l t e r n a t i v e l y , t h e a l l e l e may be s e l e c t i v e l y n e u t r a l and i t s g e o g r a p h i c p a t t e r n may be due t o p o s t g l a c i a l d i s p e r s a l ( U t t e r and A l l e n d o r f 1977, U t t e r e t a l . 1980). Among t h e t h r e e s t u d y p o p u l a t i o n s , Wade C r e e k ( l o w e r F r a s e r ) j u v e n i l e s p o s s e s s e d t h e most r o b u s t b o d i e s and y e t i n s u s t a i n e d swimming p e r f o r m a n c e t h e y c o n s i s t e n t l y o u t p e r f o r m e d 91 M o r r i s o n C r e e k ( V a n c o u v e r I s l a n d ) j u v e n i l e s . Wade Cree k coho make an 80km m i g r a t i o n between t h e sea and t h e i r n a t a l s t r e a m and t h i s m i g r a t i o n i s a l o n g t h e low g r a d i e n t s e c t i o n of t h e l o w e r F r a s e r V a l l e y . M o r r i s o n C r e e k coho make an even s h o r t e r f r e s h w a t e r m i g r a t i o n ( a p p r o x i m a t e l y 5-10km). The f r e s h w a t e r m i g r a t i o n r o u t e s of b o t h p o p u l a t i o n s a r e , however, e n t i r e l y w i t h i n t i d a l water i n f l u e n c e . As a r e s u l t , m i g r a t i o n d i s t a n c e may n o t be a s t r o n g s e l e c t i v e f o r c e a c t i n g on body form i n t h e s e p o p u l a t i o n s . P r e d a t i o n and A d a p t a t i o n The more r o b u s t body form of c o a s t a l j u v e n i l e s r e l a t i v e t o i n t e r i o r j u v e n i l e s was a s s o c i a t e d w i t h h i g h e r l e v e l s of b u r s t swimming p e r f o r m a n c e . The a s s o c i a t i o n between b u r s t swimming p e r f o r m a n c e and body r o b u s t n e s s may r e p r e s e n t an a l t e r n a t i v e m o r p h o l o g i c a l a d a p t a t i o n i n j u v e n i l e c o h o . Two p o s s i b l e h y p o t h e s e s may be c o n s i d e r e d t o a c c o u n t f o r t h e o b s e r v e d a s s o c i a t i o n between body form and b u r s t swimming p e r f o r m a n c e : (1) t h e more r o b u s t f o r m of t h e c o a s t a l p o p u l a t i o n s i s f o r t u i t o u s and does n o t r e p r e s e n t an a d a p t a t i o n or (2) body f o r m i n c o a s t a l p o p u l a t i o n s i s a r e s u l t o f s e l e c t i o n but i t i s s e l e c t i o n t h a t f a v o u r s r o b u s t - b o d i e d j u v e n i l e s i n t h e " c o a s t a l " e n v i ronment. One s e l e c t i v e f o r c e t h a t m i g h t p r o d u c e a c t i n g t o p r o d u c e l a r g e r , more r o b u s t - b o d i e d j u v e n i l e s i n c o a s t a l a r e a s i s 92 p r e d a t i o n . In f i s h e s , m o r p h o l o g i c a l r e s p o n s e s t o d i f f e r e n t i a l p r e d a t i o n p r e s s u r e have been s u g g e s t e d by v a r i o u s w o r k e r s ( L a r s o n 1976; M c P h a i l 1977; Reimchen 1980; R e i s t 1980a, 1980b). F u r t h e r , b u r s t swimming p e r f o r m a n c e a p p e a r s t o be d i r e c t l y r e l a t e d t o t h e a b i l i t y t o e s c a p e p r e d a t o r s ( R e s u l t s ; Webb 1981; Webb and C o r o l l a 1981) and b o t h body s i z e and body shape a r e i m p o r t a n t v a r i a b l e s i n d e f i n i n g l e v e l s of e s c a p e p e r f o r m a n c e ( R e s u l t s ; Weihs 1973; Webb 1978a). P o t e n t i a l and known p r e d a t o r s on j u v e n i l e s a l m o n i d s i n f r e s h w a t e r o r e s t u a r i n e a r e a s a r e l i s t e d i n T a b l e 24. C o a s t a l s t r e a m s , c l o s e t o e s t u a r i e s may have more p r e d a t o r s p e c i e s t h a n i n t e r i o r s t r e a m s , p r i m a r i l y t h r o u g h t h e i n c l u s i o n o f c e r t a i n c o t t i d and b i r d s p e c i e s . F u r t h e r , s p e c i e s w h i c h a r e d i s t r i b u t e d b o t h i n c o a s t a l and i n t e r i o r s t r e a m s may, f o r v a r i o u s r e a s o n s , be more w i d e s p r e a d i n c o a s t a l a r e a s . F o r i n s t a n c e , b o t h c u t t h r o a t t r o u t and s t e e l h e a d t r o u t may be more numerous i n c o a s t a l a r e a s ( i . e. e a s t of t h e C a s c a d e M o u n t a i n s ) t h a n i n i n t e r i o r a r e a s (Lee e t a l . 1980). Coho salmon p o p u l a t i o n s a r e c e r t a i n l y more numerous i n c o a s t a l a r e a s t h a n i n t h e i n t e r i o r ( A r o and S h e p h e r d 1967) and coho s m o l t s a r e w e l l documented as p r e d a t o r s on coho f r y ( S c o t t and Crossman 1973). C o a s t a l s t r e a m s , l o c a t e d n e a r t h e e n d p o i n t of s m o l t m i g r a t i o n s , a l s o a r e s u b j e c t t o l a r g e , t r a n s i e n t i m p u t s o f p o t e n t i a l l y p r e d a t o r y coho, c h i n o o k , s t e e l h e a d , c u t t h r o a t and D o l l y V a r d e n c h a r r , S a l v e l i n u s malma, ( L a g l e r and W r i g h t 1962; S c o t t and Crossman 1973; Meacham and C l a r k 1979). T a b l e 18. L i s t of documented o r p o t e n t i a l f i s h and b i r d p r e d a t o r s on p u v e n i l e coho salmon and t h e i r r e l a t i v e d i s t r i b u t i o n s i n B r i t i s h C o l u m b i a . D i s t r i b u t i o n i n d i c a t e s a r e a of g r e a t e r r e l a t i v e abundance; C = C o a s t a l , I c I n t e r i o r . A u t h o r i t y d e n o t e s s o u r c e of p r e d a t i o n c i t a t i o n . P r e d a t o r S p e c i e s D i s t r i b u t i o n A u t h o r i t y F i s h L e p t o c o t t u s a r m a t u s C * C o t t u s a s p e r C C. a l e u t i c u s C C. r h o t h e u s I ** P t v o c h e i l u s o r e q o n e n s i s C-I Salmo c l a r k i c l a r k i C S. q a i r d n e r i ( s t e e l h e a d ) C S. g a i r d n e r i - ( r e s i d e n t s ) C-I S a l v e l i n u s tnalma C c o n f l u e n t u s I O n c o r h y n c h u s k i s u t c h C L a m p e t r a macrostoma C L o t a l o t a I Mace (1983) S c o t t and Crossman (1973) I b i d , P a t t e n (1975) I b i d , P a t t e n (1975) S c o t t end Crossman (1973) I b i d I b i d , S h a p o v a l o v and T a f t (1954) I b i d , S h a p o v a l o v and T a f t (1954) I b i d , L a g l e r and W r i g h t (1962) ? I b i d , S h a p o v a l o v a nd T a f t (1954) B e a m i s h (1982) L a r s s o n and L a r s s o n ( 1 9 75) + B i r d s G a v i a spp. P o d i c e p s spp. Merqus s p p . P h a l a c r o c o r a x s p p . A r d e a h e r o d i a s  L a r u s p h i l a d e l p h i a  L. q l a u c e s c e n s L. c a n u s "Sterna p a r a d i s a e a C c •> c c c c c c Mace I b i d I b i d I b i d I b i d I b i d I b i d Mace I b i d ( 1983) , E l s o n (1962) Mossman (1959) Mossman (1959) (1983) Mossman (1959) * e s t u a r i n e ** C-I i n C o l u m b i a R i v e r S y s t e m + r e c o r d e d f o r A t l a n t i c s a l m o n 94 The p r e d a t o r y impact of c e r t a i n b i r d s p e c i e s on j u v e n i l e s a l m o n i d s a l s o may be s u b s t a n t i a l ( E l s o n 1962; Mace 1983). In terms of number of p r e d a t o r s and abundance, t h e s t a n d i n g c r o p of p o t e n t i a l l y p r e d a t o r y b i r d s i s p r o b a b l y h i g h e r i n c o a s t a l r e g i o n s t h a n i n i n t e r i o r r e g i o n s (Munro and Cowan 1947). In a d d i t i o n , t h e p r o x i m i t y o f c o a s t a l s t r e a m s t o c o a s t a l m i g r a t i o n r o u t e s of p i s c i v o r o u s b i r d s s u c h as t h e A r c t i c l o o n , S t e r n a  p a r a d i s a e a , and m e r g a n s e r s , Mergas spp, may l e a d t o l a r g e f e e d i n g a g g r e g a t i o n s o f b i r d s . Mace (1983) n o t e d o v e r 2,300 p i s c i v o r o u s b i r d s on a s i n g l e o c c a s i o n a t t h e B i g Q u a l i c u m R i v e r e s t u a r y . T h i s e s t u a r y i s o n l y 0.14 s q . km i n a r e a and t h e c o n c e n t r a t i o n of b i r d s o c c u r r e d d u r i n g t h e seaward m i g r a t i o n o f h a t c h e r y r e a r e d c h i n o o k salmon s m o l t s . P i s c i v o r o u s b i r d s removed between 2 and 25 p e r c e n t o f h a t c h e r y r e l e a s e s of coho and c h i n o o k s m o l t s (Mace 1983). Thus t h e p o t e n t i a l f o r p r e d a t i o n on j u v e n i l e s a l m o n i d s i s e s t u a r i n e a r e a s i s c o n s i d e r a b l e . B o t h t h e r e s u l t s o f my s i z e - a t - e m e r g e n c e e x p e r i m e n t and r e s u l t s documented by P a t t e n (1975, 1977) d e m o n s t r a t e t h a t l a r g e r , more r o b u s t j u v e n i l e s a l m o n i d s have r e d u c e d s u s c e p t i b i l i t y t o p r e d a t i o n . The r e l a t i v e l y g r e a t e r body d e p t h i n c o a s t a l c oho may, e i t h e r t h r o u g h i n c r e a s e d b u r s t swimming p e r f o r m a n c e o r i n c r e a s e d d i f f i c u l t y i n m a n i p u l a t i o n and s w a l l o w i n g (Mace 1983), make them l e s s s u s c e p t i b l e t o p r e d a t i o n t h a n i n t e r i o r c o h o . P a t t e n (1975) d e m o n s t r a t e d t h a t i n c r e a s e d 95 s u r v i v a l f r o m t o r r e n t s c u l p i n , C o t t u s r o t h e u s , p r e d a t i o n was c o r r e l a t e d w i t h i n c r e a s e d body r o b u s t n e s s i n f o u r O n c o r h y n c h u s s p e c i e s and s t e e l h e a d t r o u t . I n t e r e s t i n g l y , j u v e n i l e coho salmon s u r v i v e d p r e d a t o r y e n c o u n t e r s a t t h e h i g h e s t r a t e (76 p e r c e n t ) and a l s o p o s s e s s e d t h e g r e a t e s t body r o b u s t n e s s ( P a t t e n 1975). F u r t h e r m o r e , p i n k ( O n c o r h y n c h u s g o r b u s c h a ) and chum ( O n c o r h y n c h u s k e t a ) salmon s u r v i v e d p r e d a t i o n a t s u b s t a n t i a l l y l o w e r l e v e l s (2-5 p e r c e n t ) , and P a t t e n p a r t i a l l y a s c r i b e d t h e d i f f e r e n c e s i n s u r v i v a l between c o h o , p i n k and chum salmon t o t h e s l i m m e r body form of t h e l a t t e r two s p e c i e s . Body form i n i n t e r i o r coho would a l s o be e x p e c t e d t o be under s e l e c t i v e p r e s s u r e s f o r a n t i - p r e d a t o r c h a r a c t e r s , but i n i n t e r i o r p o p u l a t i o n s " p r e d a t i o n " s e l e c t i o n f o r i n c r e a s e d body r o b u s t n e s s must be t r a d e d o f f a g a i n s t s e l e c t i o n f o r a body form w h i c h m i n i m i z e s d r a g e f f e c t s . Thus s e l e c t i o n f o r s t r e a m l i n i n g may be s t r o n g e r i n i n t e r i o r p o p u l a t i o n s t h a n s e l e c t i o n f o r m o r p h o l o g i c a l a n t i p r e d a t o r a d a p t a t i o n s ; whereas s e l e c t i o n i n c o a s t a l p o p u l a t i o n s i s s t r o n g e r f o r a n t i p r e d a t o r a d a p t a t i o n s t h a n f o r s t r e a m l i n i n g . Egg s i z e v a r i a t i o n may a l s o i n d i c a t e d i f f e r e n t s e l e c t i o n p r e s s u r e s a c t i n g on body form and body s i z e i n c o a s t a l and i n t e r i o r c o ho p o p u l a t i o n s . I n t e r i o r p o p u l a t i o n s g e n e r a l l y have s m a l l e r eggs t h a n c o a s t a l p o p u l a t i o n s ( T a y l o r u n p u b l . d a t a ) . T h i s s u g g e s t s t h a t f r y s i z e - a t - e m e r g e n c e i s s m a l l e r i n i n t e r i o r p o p u l a t i o n s ( B a g e n a l 1969). Reduced p r o p o r t i o n a l gonad 96 p r o d u c t i o n has been s u g g e s t e d t o be n e g a t i v e l y c o r r e l a t e d w i t h t h e " e n v i r o n m e n t a l c o s t " o f t h e spawning m i g r a t i o n i n O n c o r h y n c h u s ( S c o t t 1962) and i n o t h e r anadromous f i s h e s ( G l e b e and L e g g e t t 1976; L e g g e t t and C a r s c a d d e n 1978). The p r o p o s e d l o w e r l e v e l s of p r e d a t i o n i n i n t e r i o r a r e a s may make an e n e r g e t i c t r a d e o f f p o s s i b l e i n i n t e r i o r s t o c k s , whereby f r y s i z e - a t - e m e r g e n c e (= p r e y e s c a p e a b i l i t y ) i s s a c r i f i c e d ( t h r o u g h t h e p r o d u c t i o n o f s m a l l e r eggs) f o r e n e r g e t i c c o n s i d e r a t i o n s . S t r o n g e v i d e n c e f o r an a d a p t i v e b a s i s t o f e a t u r e s o f body m o r p h o l o g y and body s i z e of j u v e n i l e coho have been p r e s e n t e d i n t h i s t h e s i s . S e l e c t i o n i n i n t e r i o r p o p u l a t i o n s i s seen as p r i m a r i l y t h r o u g h s e l e c t i o n f o r f e a t u r e s m a x i m i z i n g e n e r g e t i c c o n s i d e r a t i o n s ( d e c r e a s e d r o b u s t n e s s , s m a l l e r eggs) i n r e s p o n s e t o t h e s e l e c t i v e a s p e c t s of l o n g and d i f f i c u l t f r e s h w a t e r m i g r a t i o n r o u t e s . In c o n t r a s t , i n c o a s t a l p o p u l a t i o n s s e l e c t i o n may a c t f o r i n c r e a s e d body r o b u s t n e s s and body s i z e i n j u v e n i l e s i n r e s p o n s e t o l o n g t e r m e x p o s u r e t o h i g h e r r e l a t i v e p r e d a t i o n i n c o n j u n c t i o n w i t h r e d u c e d h y d r o d y n a m i c c o n s t r a i n t s . In e i t h e r c a s e , t h e r e s u l t s of t h i s r e s e a r c h c l e a r l y i n d i c a t e t h a t c o a s t a l and i n t e r i o r c o h o salmon a r e v e r y d i f f e r e n t w i t h r e s p e c t t o c r i t i c a l a s p e c t s of t h e i r b i o l o g y . The p o p u l a t i o n c h a r a c t e r i s t i c s e x p l o r e d i n t h i s t h e s i s a r e s u g g e s t e d t o be t h e r e s u l t o f n a t u r a l s e l e c t i o n . I f f i t n e s s l e v e l s o f i n d i v i d u a l s i n m a n i p u l a t e d p o p u l a t i o n s a r e t o a p p r o a c h t h o s e i n n a t u r e , f i s h e r i e s managers s h o u l d e n d e a v o r t o m a i n t a i n 97 t h e s e c h r a c t e r i s t i c s a t l e a s t a t t h e l e v e l of c o a s t a l - i n t e r i o r d i f f e r e n c e s , d u r i n g a r t i f i c i a l enhancement p r o j e c t s . 98 LITERATURE CITED Anas, R.E. and S. M u r a i . 1969. Use of s c a l e c h a r a c t e r s and a d i s c r i m i n a n t f u n c t i o n f o r c l a s s i f y i n g s o c k e y e salmon ( O n c o r h y n c h u s n e r k a ) by c o n t i n e n t of o r i g i n . I n t e r n . N o r t h P a c . F i s h . Comm. B u l l . No. 26:157-192. A r g u e , A.W., R. H i l b o r n , R.M. Peterman, M.J. S t a l e y and C . J . W a l t e r s . 1983. S t r a i t of G e o r g i a c h i n o o k and coho f i s h e r y . Can. D e p t . F i s h , and Oceans B u l l . F i s h . A q u a t . S c i . No. 211. 91 pp. A r o , K.V. and M.P. S h e p a r d . 1967. Spawning p o p u l a t i o n s o f N o r t h P a c i f i c s a lmon: P a c i f i c salmon i n Canada. I n t e r n . N o r t h P a c i f i c F i s h . Comm. B u l l . No. 23:225-327. B a g e n a l , T.B. 1969. R e l a t i o n s h i p between egg s i z e and f r y s u r v i v a l i n brown t r o u t , Salmo t r u t t a L . J . F i s h . B i o l . J_: 349-353. Bams, R.A. 1967. D i f f e r e n c e s i n p e r f o r m a n c e o f n a t u r a l l y and a r t i f i c i a l l y p r o p a g a t e d s o c k e y e salmon m i g r a n t f r y as measured w i t h swimming and p r e d a t i o n t e s t s . J . F i s h . Res. Bd. Canada 24:1117-1153. Bams, R.A. 1976. S u r v i v a l and p r o p e n s i t y f o r homing a s a f f e c t e d by p r e s e n c e or a b s e n c e o f l o c a l l y a d a p t e d p a t e r n a l genes i n two t r a n s p l a n t e d p i n k salmon p o p u l a t i o n s . J . F i s h . Res. Bd. Canada 33:2716-2725. Banks, 1969. A r e v i e w o f t h e l i t e r a t u r e on t h e u p s t r e a m m i g r a t i o n of a d u l t s a l m o n i d s . J . F i s h . B i o l . J_:85-1 36. B a r b e r , F.G. 1983. I n s h o r e m i g r a t i o n of a d u l t F r a s e r s o c k e y e , a s p e c u l a t i o n . Can. D e p t . F i s h . Oceans T e c h . R e p t . F i s h . A q u a t . S c i . No. 1162. 14 pp. Ba r l o w , G.W. 1961. The c a u s e s and s i g n i f i c a n c e of m o r p h o l o g i c a l v a r i a t i o n i n f i s h e s . S y s t . Z o o l . 10:105-117. 99 Beacham, T.D. and P . J . S t a r r . 1982. P o p u l a t i o n b i o l o g y o f chum salmon, O n c o r h y n c h u s k e t a , from t h e F r a s e r R i v e r , B r i t i s h C o l u m b i a . F i s h . B u l l . 80:813-825. Beamish, F.W. 1978. Swimming c a p a c i t y . Pages 101-187 I_n W.S. Hoar and D . J . R a n d a l l [ e d i t o r s . ] F i s h p h y s i o l o g y . Volume V I I . A cademic P r e s s L t d , New Y o r k . Beamish, R . J . 1982. L a m p e t r a macrostoma , a new s p e c i e s of f r e s h w a t e r p a r a s i t i c l a m p r e y from t h e west c o a s t of Canada. Can. J . F i s h . A q u a t . S c i . 39:736-747. Behnke, R . J . 1981. S y s t e m a t i c s and z o o g e o g r a p h i c a l i n t e r p r e t a t i o n o f G r e a t B a s i n t r o u t s . Pages 95-124, I n : R . J . Naiman and D.L. S o l t z [ e d i t o r s . ] F i s h e s i n N o r t h A m e r i c a n d e s e r t s . W i l e y , New Y o r k . B e s n e r , M. and L.S. S m i t h . 1983. M o d i f i c a t i o n of swimming mode and s t a m i n a i n two s t o c k s of coho salmon ( O n c o r h y n c h u s  k i s u t c h ) by d i f f e r i n g l e v e l s of l o n g - t e r m c o n t i n u o u s e x e r c i s e . Can. J . F i s h . A q u a t . S c i . 40:733-739. B i l l i n g s l e y , L.W. [ e d i t o r . ] 1981. P r o c e e d i n g s o f t h e s t o c k c o n c e p t i n t e r n a t i o n a l symposium. Can. J . F i s h . A q u a t . S c i . 38:1457-1923. B i l t o n , H.T. 1971. I d e n t i f i c a t i o n o f major B.C. and A l a s k a r u n s of even y e a r and odd y e a r p i n k salmon from s c a l e c h a r a c t e r s . J . F i s h . Res. Bd. Canada 29:295-301. B l a k e , R.W. 1979. I n f l u e n c e o f p e c t o r a l f i n shape on t h r u s t and d r a g i n l a b r i f o r m l o c o m o t i o n . J . Z o o l . ( L o n d o n ) 194:53-66. B l a k e , R.W. 1983a. F u n c t i o n a l d e s i g n and b u r s t - a n d - c o a s t swimming i n f i s h e s . Can. J . Z o o l . 61:2491-2494. B l a k e , R.W. 1983b. Swimming i n t h e e l e c t r i c e e l s and k n i f e f i s h e s . Can. J . Z o o l . 61:1432-1441. B l a k e , R.W. 1983c. F i s h l o c o m o t i o n . Cambridge U n i v e r s i t y P r e s s , C a m b r i d g e , E n g l a n d . 208 pp. 100 B l a k e , R.W. 1983d. I n t r o d u c t i o n t o f l u i d d y n a m i c s . U n p u b l . MS. 25 pp. B l a k e , R.W. I983e. A r e v i e w of a s p e c t s of t u r b u l e n t f l o w p e r t i n e n t t o f i s h swimming p e r f o r m a n c e . U n p u b l . MS. 19 pp. B l i s s , C . I . 1937. The c a l c u l a t i o n of t h e t i m e - m o r t a l i t y c u r v e . Ann. A p p l . B i o l . 24:815-852. Bock, W.J. 1980. The d e f i n i t i o n and r e c o g n i t i o n o f b i o l o g i c a l a d a p t a t i o n . Amer. Z o o l . 20:217-227. B r e d e r , C M . 1926. The l o c o m o t i o n of f i s h e s . Z o o l o g i c a (N.Y.) 4: 159-297. B r e t t , J.R. 1967. Swimming p e r f o r m a n c e of s o c k e y e salmon ( O n c o r h y n c h u s n e r k a ) i n r e l a t i o n t o f a t i g u e t i m e and t e m p e r a t u r e . J . F i s h . Res. Bd. Canada 24:1731-1741. B r e t t , J.R. 1983. The swimming s p e e d of a d u l t p i n k salmon, O n c o r h y n c h u s g o r b u s c h a , a t 20 C and a c o m p a r i s o n w i t h s o c k e y e s a l m o n , 0. n e r k a . Can. T e c h . R p t . F i s h . A q u a t . S c i . No. 1143. 37 p. C a r s c a d d e n , J . E . and W.C. L e g g e t t . 1975. M e r i s t i c d i f f e r e n c e s i n spawning p o p u l a t i o n s of A m e r i c a n shad, A l o s a s a p i d i s s i m a : e v i d e n c e f o r homing t o t r i b u t a r i e s o f t h e S t . John River,New B r u n s w i c k . J . F i s h . Res. Bd. Canada 32:653-660. C o l b y , P . J . and S . J . N e p s z y . 1981. V a r i a t i o n among s t o c k s o f w a l l e y e ( S t i z o s t e d i o n v i t r e u m v i t r e u m ) : management i m p l i c a t i o n s . Can. J . F i s h . A q u a t . S c i . 38:1814-1831. C o l l i n s , G. 1958. The measurement of p e r f o r m a n c e o f salmon i n f i s h w a y s . Pages 51-91 I_n P.A. L a r k i n [ e d i t o r . ] The i n v e s t i g a t i o n of f i s h - p o w e r p r o b l e m s . H.R. M a c M i l l i a n l e c t u r e s i n f i s h e r i e s . U n i v . o f B r i t i s h C o l u m b i a , V a n c o u v e r , Canada. 111 pp. D i x o n , W.J. [ e d i t o r . ] 1981. BMDP s t a t i s t i c a l s o f t w a r e . UCLA P r e s s . 880 pp. 101 E l s o n , P.F. 1962. P r e d a t o r - p r e y r e l a t i o n s h i p s between f i s h -e a t i n g b i r d s and A t l a n t i c salmon ( w i t h a s u p p l e m e n t on f u n d a m e n t a l s of m e r g a n s e r c o n t r o l ) . F i s h . Res. Bd. Canada B u l l . No. 133. 87 pp. E v r o p e i t s e v a , N.V. 1962. C o m p a r a t i v e a n a l y s i s o f t h e d e s m o l t i f i c a t i o n p r o c e s s among t h e young of d i f f e r e n t e c o l o g i c a l forms o f A t l a n t i c s a l m o n . Uch. Zap. L e n i n g r . Gos. U n i v . 311:46-73. ( F i s h . Res. Bd. T r a n s l . S e r . 4 3 1 ) . F e s s l e r , J . L . and H.F. Wagner. 1969. Some m o r p h o l o g i c a l and b i o c h e m i c a l c h a n g e s i n s t e e l h e a d t r o u t d u r i n g t h e p a r r -s m o l t t r a n s f o r m a t i o n . J . F i s h . Res. Bd. Canada 26:2823-2841 . F i n n e y , D . J . 1971. P r o b i t a n a l y s i s . 3 r d e d i t i o n . Cambridge U n v e r s i t y P r e s s . C a m b r i d g e , E n g l a n d . F o u r n i e r , P.A., B. R i d d e l l amd C. B u s a c k . 1984. E s t i m a t i n g s t o c k c o m p o s i t i o n i n m i x e d s t o c k f i s h e r i e s u s i n g m o r p h o m e t r i c , m e r i s t i c and e l e c t r o p h o r e t i c c h a r a c t e r s . Can. J . F i s h . A q u a t . S c i . 4]_: 400-408. Fox, D.L. and K.E. G u l r e . 1976. D o c u m e n t a t i o n f o r MIDAS. S t a t i s t i c a l r e s e a r c h l a b o r a t o r y , U n i v e r s i t y of M i c h i g a n , Ann A r b o u r , M i c h i g a n . 3 r d . E d i t i o n . 203 pp. F r a s e r , F . J . , P . J . S t a r r and A.Y. F e d o r e n k o . 1982. A r e v i e w of t h e c h i n o o k and c oho salmon of t h e F r a s e r R i v e r . Can. T e c h . R p t . F i s h . A q u a t . S c i . No. 1126. 130 pp. G a t z , A . J . 1979. E c o l o g y and m o r p h o l o g y of f r e s h w a t e r s t r e a m f i s h e s . T u l a n e S t u d i e s i n B o t a n y and Z o o l o g y 21:91 -123. Geen, G.H. 1975. E c o l o g i c a l c o n s e q u e n c e s o f t h e p r o p o s e d Moran Dam on t h e F r a s e r R i v e r . J . F i s h . Res. Bd. Canada 32:126-1 35. G i l h o u s e n , P. 1980. E n e r g y s o u r c e s and e x p e n d i t u r e s i n F r a s e r R i v e r s o c k e y e salmon d u r i n g t h e i r s pawning m i g r a t i o n . I n t e r . P a c . Salmon Comm. B u l l . No. 22: 51 pp. 1 02 G l e b e , B.D. and W.C. L e g g e t t . 1976. Weight l o s s and e n e r g y e x p e n d i t u r e of A m e r i c a n shad d u r i n g t h e f r e s h w a t e r m i g r a t i o n . F i n a l R e p t . P r o g . AFC-8, U.S. Nat. Mar. F i s h . S e r . G o l d , J.R. 1977. S y s t e m a t i c s of w e s t e r n N o r t h A m e r i c a n t r o u t ( S a l m o ) , w i t h n o t e s on t h e r e d b a n d t r o u t of Sheepheaven C r e e k , C a l i f o r n i a . Can. J . Z o o l . 55:1858-1873. G o u l d , S . J . and J.T J o h n s t o n . 1972. G e o g r a p h i c v a r i a t i o n . Ann Rev. E c o l . S y s t . 3_:489-456. G r a n t , W.S. and F.M. U t t e r . 1980. B i o c h e m i c a l g e n e t i c v a r i a t i o n i n w a l l e y e p o l l o c k , T h e r a g r a chalcogramma: p o p u l a t i o n s t r u c t u r e i n t h e s o u t h e a s t e r n B e r i n g Sea and t h e G u l f o f A l a s k a . Can. J . F i s h . A q u a t . S c i . 37:1093-1100. Hagen, D.W. 1973. I n h e r i t a n c e i n number o f l a t e r a l p l a t e s and g i l l r a k e r s i n G a s t e r o s t e u s a c u l e a t u s . H e r e d i t y 30:303-312. Hartman, G.F. 1965. The r o l e of b e h a v i o u r i n t h e e c o l o g y and i n t e r a c t i o n o f u n d e r y e a r l i n g coho salmon and s t e e l h e a d t r o u t . J . F i s h . Res. Bd. Canada 22:1035-1081. H e a l y , M.C. 1983. C o a s t w i d e d i s t r i b u t i o n and ocean m i g r a t i o n p a t t e r n s of s t r e a m - and o c e a n - t y p e c h i n o o k salmon, O n c o r h y n c h u s t s h a w y t s c h a . Can. F i e l d N a t . 97:427-433. H j o r t , R.C. and B. S c h r e c k . 1982. P h e n o t y p i c d i f f e r e n c e s among w i l d and h a t c h e r y s t o c k s o f coho salmon i n Oregon, W a s h i n g t o n and C a l i f o r n i a . F i s h . B u l l . 80:105-119. Howard, T.E. 1973. E f f e c t s of k r a f t m i l l e f f l u e n t s on t h e swimming s t a m i n a , t e m p e r a t u r e t o l e r a n c e and r e s p i r a t i o n i n some s a l m o n i d f i s h . D o c t o r a l D i s s e r t a t i o n , U n i v e r s i t y o f S t r a t h c l y d e , Glasgow, S c o t l a n d . 183 pp. Hubbs, C L . K. F. L a g l e r . 1967. F i s h e s o f t h e G r e a t L a k e s r e g i o n . U n i v . o f M i c h i g a n P r e s s , Ann A r b o u r , M i c h i g a n . 213 PP. 1 03 I d l e r , D.R. and W.A. Cl e m e n s . 1959. The e n e r g y e x p e n d i t u r e of F r a s e r R i v e r s o c k e y e salmon d u r i n g m i g r a t i o n , spawning and d e a t h . P r o g . R e p t . I n t . Pac. Salmon F i s h . Comm. No. 6. 80 pp. I h s s e n , P.E. and J . S . T a i t . 1974. G e n e t i c d i f f e r e n c e s i n r e t e n t i o n of s w i m b l a d d e r gas i n two p o p u l a t i o n s of l a k e t r o u t ( S a l v e l i n u s n a m a y c u s h) . J . F i s h . Res. Bd. Canada 31: 1351-1354. I h s s e n , P.E., D.O. E v a n s , W.J. C h r i s t i e , J.A. Reckahn and R.L. D e s j a r d i n e . 1981. L i f e h i s t o r y , m o r p h o l o g y and e l e c t r o p h o r e t i c c h a r a c t e r i s t i c s of f i v e a l l o p a t r i c s t o c k s of l a k e w h i t e f i s h ( C o r e g o n u s c l u p e i f o r m i s ) i n t h e G r e a t L a k e s r e g i o n . Can. J . F i s h . A q u a t . S c i . 38:1790-1807. I h s s e n , P.E.,H.E. Booke,J.M. C a s s e l m a n , J . M . McGlade,N.R. Payne and F.M. U t t e r . 1981. S t o c k i d e n t i f i c a t i o n : m a t e r i a l s and methods. Can. J . F i s h . A q u a t . S c i . 38:1838-1855. J o n e s , F.R.H. 1962. F i s h m i g r a t i o n . New Y o r k : S t . M a r t i n s . 325 pp. Kanep, S.V. 1971. Some a s p e c t s o f t h e f u n c t i o n a l m o r p h o l o g y of th e l a k e p e l y a d ( C o r e g o n u s p e l e d [ G m e l i n ] ) . V o p r o . I c h t h y o l . _n:855-866. J o h n s o n , N.L. and S. K o t z . 1970. D i s t r i b u t i o n s i n s t a t i s t i c s . 1. C o n t i n u o u s u n i v a r i a t e d i s t r i b u t i o n s . Houghton M i f f l i n , New Y o r k . 338 pp. L a g l e r , K. and A.T. W r i g h t . 1962. P r e d a t i o n by D o l l y V a r d e n , S a l v e l i n u s malma, on young salmon, O n c o r h y n c h u s spp., i n an e s t u a r y i n s o u t h e a s t A l a s k a . T r a n s . Am. F i s h . S o c . 91: 90-93. L a r k i n , P.A. 1972. The s t o c k c o n c e p t and management o f P a c i f i c s a l m o n . Pages 11-15. I_n: R.C. Simon and P.A. L a r k i n [ e d i t o r s . ] The s t o c k c o n c e p t i n P a c i f i c s a l m o n . H.R. M a c M i l l a n L e c t u r e s i n F i s h e r i e s , U n i v e r s i t y o f B r i t i s h C o l u m b i a , V a n c o u v e r , Canada 1 04 L a r s o n , G.E. 1976. S o c i a l b e h a v i o u r and f e e d i n g a b i l i t y of two p h e n o t y p e s of G a s t e r o s t e u s a c u l e a t u s i n r e l a t i o n t o t h e i r s p a t i a l and t r o p h i c s e g r e g a t i o n i n a t e m p e r a t e l a k e . Can. J . Z o o l . 54:107-121. L e e , D.S., C R . G i l b e r t , C H . H o c u t t , R.E. J e n k i n s , D.E. M c A l l i s t e r and J.R. S t a u f f e r J r . 1980. A t l a s of N o r t h A m e r i c a n f r e s h w a t e r f i s h e s . N o r t h C a r o l i n a B i o l o g i c a l S u r v e y P u b l . No. 1980-12, 854 pp. L e g g e t t , W.C. and J . E . C a r s c a d d e n . 1978. L a t i t u d i n a l v a r i a t i o n i n r e p r o d u c t i v e c h a r a c t e r i s t i c s of A m e r i c a n shad ( A l o s a  s a p i d i s s i m a ) : e v i d e n c e f o r p o p u l a t i o n s p e c i f i c l i f e h i s t o r y s t r a t e g i e s i n f i s h . J . F i s h . Res. Bd. Canada 35: 1469-1478. Mace, P.M. 1983. B i r d p r e d a t i o n on j u v e n i l e chum salmon i n t h e B i g Q u a l i c u m R i v e r e s t u a r y . A p p e n d i x 1. D o c t o r a l D i s s e r t a t i o n , U n i v e r s i t y o f B r i t i s h C o l u m b i a , V a n c o u v e r , Canada. M a c l e a n , J.A. and D.O. E v a n s . 1981. The s t o c k c o n c e p t , d i s c r e t e n e s s of f i s h s t o c k s and f i s h e r i e s management. Can. J . F i s h . A q u a t . S c i . 38:1889-1898. Mason, J. C . 1976. Some f e a t u r e s o f coho salmon, O n c o r h y n c h u s k i s u t c h , f r y e m e r g i n g from s i m u l a t e d r e d d s and c o n c u r r e n t c h a n g e s i n p h o t o b e h a v i o u r . F i s h . B u l l . 74:167-175. M c A l l i s t e r , D.E. and C.C. L i n d s e y . 1959. S y s t e m a t i c s o f t h e f r e s h w a t e r s c u l p i n s ( C o t t u s ) o f B r i t i s h C o l u m b i a . N a t . Mus. Can. B u l l . C o n t r i b . Z o o l . No. 172:66-89. M c B r i d e , D.N. and S.L. M a r s h a l l . 1983. F e a s i b i l i t y of s c a l e p a t t e r n a n a l y s i s t o i d e n t i f y t h e o r i g i n s o f c h i n o o k salmon ( O n c o r h y n c h u s t s h a w y t s c h a Walbaum) i n t h e l o w e r Yukon R i v e r c o m m e r c i a l g i l l n e t f i s h e r y , 1980-1981. A l a s k a D e p t . F i s h and Game I n f o r m a t i o n L e a f l e t No. 208. 64 pp. M cDonald, J . 1981. The s t o c k c o n c e p t and i t s a p p l i c a t i o n t o B r i t i s h C o l u m b i a salmon f i s h e r i e s . Can. J . F i s h . A q u a t . S c i . 38:1657-1664. 1 05 McGregor, A . J . 1983. A b i o c h e m i c a l g e n e t i c a n a l y s i s of p i n k salmon ( O n c o r h y n c h u s g o r b u s c h a ) from s e l e c t e d s t r e a m s of n o r t h e r n S o u t h e a s t A l a s k a . A l a s k a D e p t . of F i s h and Game I n f o r m a t i o n L e a f l e t No. 213. 70 pp. M c P h a i l , J.D. 1977. I n h e r i t e d d i f f e r e n c e s i n t h e s i z e a t f i r s t s p a w n i n g among s t i c k l e b a c k s . H e r e d i t y 38:53-60. M c P h a i l , J.D. 1984. E c o l o g y and e v o l u t i o n o f s y m p a t r i c s t i c k l e b a c k s ( G a s t e r o s t e u s ) : m o r p h o l o g i c a l and g e n e t i c e v i d e n c e f o r a s p e c i e s p a i r i n Enos L a k e , B r i t i s h C o l u m b i a . Can. J . Z o o l . 62:, In p r e s s . Meacham, C P . and J.H. C l a r k . 1979. Management t o i n c r e a s e anadromous salmon p r o d u c t i o n . Pages 377-385 In.: H. C l e p p e r and R. S t r o u d [ e d i t o r s . ] P r e d a t o r - p r e y s y s t e m s i n f i s h e r i e s managment. S p o r t F i s h . I n s t . S p e c . P u b l . , W a s h i n g t o n , D . C 504 pp. M u l l i g a n , T . J . , L. L a p i , R. K i e s e r , S.B. Yamada and D.L. Duewer. 1983. Salmon s t o c k i d e n t i f i c a t i o n b a s e d upon e l e m e n t a l c o m p o s i t i o n of v e r t e b r a e . Can. J . F i s h . A q u a t . S c i . 40: 215-229. Munro, J.A. and I . McT. Cowan. 1947. A r e v i e w o f t h e b i r d f a u n a of B r i t i s h C o l u m b i a . B r i t . C o l . P r o v . Mus. Spec. P u b l . No. 2., V i c t o r i a , Canada. 285 pp. M u r r a y , C.B. 1980. Some e f f e c t s o f t e m p e r a t u r e on z y g o t e and a l e v i n s u r v i v a l , r a t e of d e v e l o p m e n t and s i z e a t emergence of P a c i f i c salmon and r a i n b o w t r o u t . M.Sc. t h e s i s , U n i v e r s i t y of B r i t i s h C o l u m b i a , V a n c o u v e r , B.C. 156 pp. N i , I-H. 1982. M e r i s t i c v a r i a t i o n i n bea k e d r e d f i s h , S e b a s t e s m e n t e l l a and S. f a s c i a t u s , i n t h e n o r t h w e s t A t l a n t i c . Can. J . F i s h . A q u a t . S c i . 39:1664-1685. N o r t h c o t e , T.G. and B.W. K e l s o . 1981. D i f f e r e n t i a l r e s p o n s e t o water c u r r e n t by two homozygous LDH p h e n o t y p e s o f young r a i n b o w t r o u t , Salmo g a i r d n e r i . Can. J . F i s h . A q u a t . S c i . (38,348-352) 1 06 P a r k i n s o n , E.A. 1980. G e n e t i c s t r u c t u r e of s t e e l h e a d t r o u t p o p u l a t i o n s i n B r i t i s h C o l u m b i a . M.Sc. t h e s i s . U n i v e r s i t y of B r i t i s h C o l u m b i a , V a n c o u v e r , Canada. 106 pp. P a t t e n , B.G. 1975. C o m p a r a t i v e v u n e r a b i l i t y o f P a c i f i c salmon and s t e e l h e a d t r o u t t o p r e d a t i o n by t o r r e n t s c u l p i n i n s t r e a m a q u a r i a . F i s h . B u l l . 73:931-934. P a t t e n , B.G. 1977. Body s i z e and l e a r n e d a v o i d e n c e as f a c t o r s a f f e c t i n g p r e d a t i o n on coho salmon, O n c o r h y n c h u s k i s u t c h , f r y by t o r r e n t s c u l p i n , C o t t u s r o t h e u s . F i s h . B u l l . 75: 457-459. P i m e n t e l , R.A. 1979. M o r p h o m e t r i e s : t h e m u l t i v a r i a t e a n a l y s i s of b i o l o g i c a l d a t a . K e n d a l l / H u n t P u b l i s h i n g Co. Dubuque, Iowa. 276 pp. Power, G. 1981. S t o c k c h a r a c t e r i s t i c s and c a t c h e s of A t l a n t i c salmon (Salmo s a l a r ) i n Quebec, and N e w f o u n d l a n d and L a b r a d o r i n r e l a t i o n t o e n v i r o n m e n t a l v a r i a b l e s . Can. J . F i s h . A q u a t . S c i . 38:1601-1611. Reimchen, T.E. 1980. S p i n e d e f i c i e n c y and p o l y m o r p h i s m i n a p o p u l a t i o n of G a s t e r o s t e u s a c u l e a t u s : and a d a p t a t i o n t o p r e d a t o r s ? Can. J . Z o o l . 58:1232-1244. R e i s t , J.D. 1980a. S e l e c t i v e p r e d a t i o n upon p h e n o t y p e s of b rook s t i c k l e b a c k , C u l a e a i n c o n s t a n s , by n o r t h e r n p i k e , Esox l u c i u s . Can. J . Z o o l . 58:1245-1258. R e i s t , J.D. 1980b. P r e d a t i o n upon p e l v i c p h e n o t y p e s o f b rook s t i c k l e b a c k , C u l a e a i n c o n s t a n s , by s e l e c t e d i n v e r t e b r a t e s . Can. J . Z o o l . 58:1253-1258. R i c k e r , W.E. 1950. C y c l i c dominance among F r a s e r R i v e r s o c k e y e . E c o l o g y 3J_:6-26. R i c k e r , W.E. 1972. H e r e d i t a r y and e n v i r o n m e n t a l f a c t o r s a f f e c t i n g c e r t a i n s a l m o n i d p o p u l a t i o n s . Pages 19-160. I n : R.C. Simon and P.A. L a r k i n [ e d i t o r s . ] The s t o c k c o n c e p t i n P a c i f i c s a l m o n . H.R. M a c M i l l a n L e c t u r e s i n F i s h e r i e s , U n i v e r s i t y of B r i t i s h C o l u m b i a , V a n c o u v e r , Canada. 231 pp. 1 07 R i d d e l l , B.E. and W.C. L e g g e t t . 1981. E v i d e n c e f o r an a d a p t i v e b a s i s f o r g e o g r a p h i c v a r i a t i o n i n body m o r p h o l o g y and t i m e of downstream m i g r a t i o n of j u v e n i l e A t l a n t i c salmon (Salmo  s a l a r ) . Can. J . F i s h . A q u a t . S c i . 38:308-320. R i d d e l l , B.E., W.C. L e g g e t t and R.L. S a u n d e r s . 1981. E v i d e n c e of a d a p t i v e p o l y g e n i c v a r i a t i o n between two p o p u l a t i o n s of A t l a n t i c salmon (Salmo s a l a r ) n a t i v e t o t r i b u t a r i e s o f t h e S.W. M i r a m i c h i R i v e r , N.B. Can. J . F i s h . A q u a t . S c i . 38: 321-333. Rosenau, M.L. 1984. A c o m p a r i s o n o f a g o n i s t i c b e h a v i o u r i n two p o p u l a t i o n s of j u v e n i l e c o h o salmon ( O n c o r h y n c h u s  k i s u t c h ) . M.Sc. t h e s i s , U n i v e r s i t y of B r i t i s h C o l u m b i a , V a n c o u v e r , Canada. 79 pp. S c h a f f e r , W.M. and P.F. E l s o n . 1975. The a d a p t i v e s i g n i f i c a n c e of v a r i a t i o n s i n l i f e h i s t o r y among l o c a l p o p u l a t i o n s of A t l a n t i c salmon i n N o r t h A m e r i c a . E c o l o g y 56:577-590. S c o t t , D.P. 1962. E f f e c t of f o o d q u a n t i t y on f e c u n d i t y of r a i n b o w t r o u t , Salmo g a i r d n e r i . J . F i s h . Res. Bd. Canada 19:715-731 . S c o t t , W.B. and E . J . Crossman. 1973. F r e s h w a t e r f i s h e s of . C a n ada. F i s h . Res. Bd. Canada B u l l . 173. 966 pp. S e a l , H.L. 1964. M u l t i v a r i a t e s t a t i s t i c a l a n a l y s i s f o r b i o l o g i s t s . Methuen and Co., London. 269 pp. S h a p o v a l o v , L. and A.C. T a f t . 1954. The l i f e h i s t o r i e s o f r a i n b o w t r o u t (Salmo g a i r d n e r i g a i r d n e r i ) and s i l v e r s almon ( O n c o r h y n c h u s k i s u t c h " T ~ w i t h s p e c i a l r e f e r e n c e t o W a d d e l l C r e e k , C a l i f o r n i a , and r ecommendations r e g a r d i n g t h e i r management. C a l i f . F i s h and Game B u l l . No. 98. 375 pp. Simon, R.C. and P.A. L a r k i n . [ e d i t o r s . ] 1972. The s t o c k c o n c e p t i n P a c i f i c s almon. H.R. M a c M i l l i a n L e c t u r e s i n F i s h e r i e s , U n i v e r s i t y of B r i t i s h C o l u m b i a , V a n c o u v e r , Canada. 231 pp. S n e d e c o r , G.W. and W.G. C o c h r a n . 1967. S t a t i s t i c a l methods. 6 t h e d i t i o n . , Iowa S t a t e U n i v e r s i t y P r e s s , Ames, Iowa. 593 pp. 108 S o k a l , R.R. and F . J . R o h l f . 1969. B i o m e t r y . W.H. Freeman and Co., San F r a n c i s c o . 776 pp. S p a n g l e r , G.R., A.H. B e r s t and J . F . Koonce. 1981. P e r s p e c t i v e s and p o l i c y recommendations on t h e r e l e v a n c e of t h e s t o c k c o n c e p t t o f i s h e r y management. Can. J . F i s h . A q u a t . S c i . 38:1908-1914. S t e e l , R.G. and J.H. T o r r i e . 1980. P r i n c i p l e s and p r o c e d u r e s o f s t a t i s t i c s . McGraw H i l l Book Co., New Y o r k . 633 pp. T a v e , D. 1984. G e n e t i c s of d o r s a l f i n r a y number i n t h e guppy, P o e c i l i a r e t i c u l a t a . C o p e i a 1984(1):140-144. Thomas, A.E. and M.J. Dohahoo. 1977. D i f f e r e n c e s i n swimming p e r f o r m a n c e among s t r a i n s o f r a i n b o w t r o u t (Salmo  g a i r d n e r i ) . J . F i s h . Res. Bd. Canada 34:304-306. Thomas, A.E., R.E. Burrows and H.H. Chenoweth. 1964. A d e v i c e f o r s t a m i n a measurement o f f i n g e r l i n g s a l m o n i d s . U.S. D e p t . I n t . F i s h . W l d f . S e r . Res. R p t . No. 67. 15 pp. T h o r g a a r d , G.H. 1983. Chromosomal d i f f e r e n c e s among ra i n b o w t r o u t p o p u l a t i o n s . C o p e i a 1983(3):650-662 . T h o r p e , J . E . and K.A. M i t c h e l l . 1981. S t o c k s of A t l a n t i c salmon (Salmo s a l a r ) i n B r i t a i n and I r e l a n d : d i s c r e t e n e s s and c u r r e n t management. Can. J . F i s h . A q u a t . S c i . 38:1576-1 590. T h o r p e , R.S. 1976. B i o m e t r i c a n a l y s i s o f g e o g r a p h i c v a r i a t i o n and r a c i a l a f f i n i t i e s . B i o l . Rev. 51:407-452. Todd, T.N., G.R. S m i t h and L. C a b l e . 1981. E n v i r o n m e n t a l and g e n e t i c c o n t r i b u t i o n s t o m o r p h o l o g i c a l d i f f e r e n t i a t i o n i n c i s c o e s ( C o r e g o n i n a e ) of t h e G r e a t L a k e s . Can. J . F i s h . A q u a t . S c i . 38:59-67. T s u y u k i , H. and S.N. W i l l i s c r o f t . 1977. Swimming s t a m i n a d i f f e r e n c e s between g e n o t y p i c a l l y d i s t i n c t f orms of rainbow t r o u t (Salmo g a i r d n e r i ) and s t e e l h e a d t r o u t . J . F i s h . Res. Bd. Canada 34:996-1003. 109 U t t e r , F.M. 1981. B i o l o g i c a l c r i t e r i a f o r d e f i n i t i o n o f s p e c i e s and d i s t i n c t i n t r a s p e c i f i c p o p u l a t i o n s of anadromous s a l m o n i d s under t h e U.S. E n d a n g e r e d S p e c i e s A c t of 1973. Can. J . F i s h . A q u a t . S c i . 38:1626-1635. U t t e r , F.M. and F.W. A l l e n d o r f . 1977. D e t e r m i n a t i o n o f t h e b r e e d i n g s t r u c t u r e o f s t e e l h e a d p o p u l a t i o n s t h r o u g h gene f r e q u e n c y a n a l y s i s . Pages 44-54 J_n: T . J . H a s s l e r and R.R. V a n K i r k [ e d i t o r s . ] G e n e t i c i m p l i c a t i o n s o f s t e e l h e a d management. C a l i f . Coop. F i s h . Res. U n i t , A r e a t a . U t t e r , F.M., D. Campton, S. G r a n t , G. M i l n e r , J . Seeb and L. W i s h a r d . 1980. P o p u l a t i o n s t r u c t u r e of i n d i g e n o u s s a l m o n i d s p e c i e s of t h e P a c i f i c N o r t h w e s t . Pages 285-304 I_n W. M c N e i l and D. Himswor t h [ e d i t o r s . ] S a l m o n i d e c o s y s t e m s of th e N o r t h P a c i f i c . U n i v e r s i t y of Oregon P r e s s , C o r v a l l i s , O r e g o n . V a n s t o n e , W.E. and J.R. M a r k e r t . 1968. Some m o r p h o l o g i c a l and b i o c h e m i c a l c h a n g e s i n coho salmon ( O n c o r h y n c h u s k i s u t c h ) d u r i n g p a r r - s m o l t t r a n s f o r m a t i o n . J . F i s h . Res. Bd. Canada 25:2403-2418. W a l t e r s , V. 1961. Body form and l o c o m o t i o n i n s c o m b r o i d f i s h . Amer. Z o o l . 1:143-149. Ware, D.M. 1982. Power and e v o l u t i o n a r y f i t n e s s of t e l e o s t s . Can. J . F i s h . A q u a t . S c i . 39:3-13. Webb, P.W. 1975. H y d r o m e c h a n i c s and e n e r g e t i c s of f i s h p r o p u l s i o n . Can. D e p t . F i s h . Mar. S e r . T e c h . Rpt. No. 180. 158 pp. Webb, P.W. 1976. The e f f e c t of s i z e on t h e f a s t - s t a r t p e r f o r m a n c e of ra i n b o w t r o u t , Salmo g a i r d n e r i and a c o n s i d e r a t i o n of p i s c i v o r o u s p r e d a t o r - p r e y i n t e r a c t i o n s . J . Exp. B i o l . 65:157-177. Webb, P.W. 1977. E f f e c t s o f median f i n a m p u t a t i o n on f a s t - s t a r t p e r f o r m a n c e of r a i n b o w t r o u t . J . Exp. B i o l . 68:123-135. Webb, P.W. 1978a. F a s t - s t a r t p e r f o r m a n c e and body form i n seven s p e c i e s of t e l e o s t f i s h . J . Exp. B i o l . 74:211-226• 110 Webb, P.W. 1978b. T e m p e r a t u r e e f f e c t s on a c c e l e r a t i o n p e r f o r m a n c e of rainbow t r o u t , Salmo g a i r d n e r i . J . F i s h . Res. Bd. Canada 35:1417-1422. Webb, P.W. 1981. R e s p o n s e s of n o r t h e r n a n c h o v y , E n g r a u l i s  mordax, l a r v a e t o p r e d a t i o n by a b i t i n g p l a n k t i v o r e , A m p h i p r i o n p e r c u l a . F i s h . B u l l . 79:727-735. Webb, P.W. and T.R. C o r o l l a . 1981. B u r s t swimming p e r f o r m a n c e of n o r t h e r n a n c h o v y , E n g r a u l i s mordax l a r v a e . F i s h . B u l l . 79: 143-150. Weihs, D. 1973. The mechanism of r a p i d s t a r t i n g of a s l e n d e r f i s h . B i o r h e o l o g y 10:343-350. Whelen, M.A., J.R. A r t h u r , W.R. O l m s t e a d and J.D. Morgan. 1983. S t u d i e s of spawning coho salmon ( O n c o r h y n c h u s k i s u t c h ) i n t r i b u t a r i e s of t h e S o u t h and mainstem Thompson R i v e r s , B.C. E.V.S. C o n s u l t a n t s L t d , N o r t h V a n c o u v e r , Canada. 1 W i l c o c k , J . A . and D.N. M c B r i d e . 1983. O r i g i n s o f c h i n o o k salmon ( O n c o r h y n c h u s t s h a w y t s c h a Walbaum) i n t h e Yukon R i v e r F i s h e r i e s , 1982. A l a s k a D e p t . F i s h and Game I n f o r m a t i o n a l L e a f l e t No. 226. 36 pp. W i l k , S.J.,W.G. Smith,D.E. R a l p h and J . S i b u n k a . 1980. P o p u l a t i o n s t r u c t u r e o f summer f l o u n d e r between New York and F l o r i d a b a s e d on l i n e a r d i s c r i m i n a n t a n a l y s i s . T r a n s . Amer. F i s h . S o c . 109:265-271. W i t h l e r , F.C. 1982. T r a n s p l a n t i n g P a c i f i c s a l m o n . Can. T e c h . R p t . F i s h . A q u a t . S c i . No. 1079. 27 pp. Y e v s i n , Y.N. 1976. M o r p h o l o g i c a l c h a r a c t e r i s t i c s and v a r i a b i l i t y o f l o c a l s t o c k s of t h e autumn s e a t r o u t (Salmo t r u t t a ) of t h e r i v e r s of t h e White Sea B a s i n . J . I c h t h y o l . 16:911 -921 . Y e v s i n , Y.N. 1977. M o r p h o l o g i c a l c h a r a c t e r i s t i c s and v a r i a b i l i t y of t h e summer sea t r o u t (Salmo t r u t t a ) from t h e Pulmg'a and M a l a y a Kumzhevaya R i v e r s . J . I c h t h y o l . 17:350-356. 111 APPENDIX T a b l e A.1 A d j u s t e d g e o m e t r i c means ( ± SD, mm) of c h a r a c t e r s and r e s u l t s of ANOVA f o r j u v e n i l e coho from t e n B r i t i s h Columbia p o p u l a t i o n s . O v e r a l l mean s t a n d a r d l e n g t h i s 50mm. F i n a r e a s a r e i n s q . mm. Character Laaiaua Cr* 6. B a r r l a r a R. Coldaatar R. LouI a Cr. S l l v t r d a l t Cr. Nada c r . Denanlal Cr. R l c b j Cr. Roaewall Cr. Morrison Cr. rl9.3§3) Mo. S l o n l M e a n t Dtf ferertcea Bod,d Padd Padl or* Ar* CPA TMFA Pact Palvf SNAP SHAPE BWBD PR HL HD 1 1 . 7 8 4 . 8 9 7 . 9 0 1 5 . I t J O . 9 6 6 5 . 9 2 1 1 2 . 2 7 9 . 6 5 6 . 8 ) 1 2 . 9 1 2 7 . 2 6 9.11 S . 4 8 14.52 9.19 ( 0 . 4 1 ) ( 0 . 1 7 ) ( 0 . 3 1 ) 14.. 0 6 ) ( 3 . 7 7 ) ( 6 . 1 1 ) ( 1 1 . 7 4 ) ( 0 . 4 1 ) ( 0 . 3 B ) ( 0 . 4 4 ) ( 0 . 5 0 ) ( 0 . 3 1 ) ( 0 . 2 0 ) 1 0 . 3 9 ) ( 0 . 2 9 ) 1 1 . 1 0 5 . 0 9 7 . 8 7 3 3 . 6 9 2 8 . 0 3 8 6 . 6 1 1 4 8 . 1 5 8 . 8 0 7 . 1 1 1 2 . 8 6 2 7 . 0 3 9 . 3 6 5 . 3 5 15.37 9 . 6 3 ( 0 . 4 3 ) ( 0 . 2 0 ) ( 0 . 5 5 ) ( 5 . 2 6 ) ( 4 . 4 3 ) ( 1 2 . 2 1 ) ( 2 0 . 6 5 ) ( 0 . 4 1 ) ( 0 . 3 3 ) ( 0 . 3 5 ) ( 0 . 5 3 ) ( 0 . 3 7 ) ( 0 . 2 5 ) ( 0 . 4 1 ) ( 0 . 2 8 ) 1 1 . 9 5 4 . 9 3 7 . 9 2 3 3 . 8 4 2 9 . 13 8 4 . 8 3 1 4 7 . 8 4 8 . 9 8 7 . 0 5 1 2 . 3 0 2 7 . 3 5 9 . 7 4 5 . 2 4 1 4 . 2 6 9 . 4 2 ( 0 . 4 1 ) ( 0 . 1 8 ) ( 0 . 3 3 ) ( 3 . 3 6 ) ( 2 . 8 2 ) ( 5 . 7 J ) ( 9 . 2 8 ) ( 0 . 3 0 ) ( 0 . 2 7 ) ( 0 . 3 7 ) ( 0 . 4 3 ) ( 0 . 3 8 ) ( 0 . 2 0 ) ( 0 . 2 9 ) ( 0 . 2 6 ) 1 1 . 3 6 4 . 7 0 8 . 3 4 3 7 . 0 1 3 1 . 1 5 9 5 . 2 0 1 6 3 . 5 6 9 . 2 0 7 . 2 6 1 3 . 2 4 2 7 . 4 0 8.61 5 . 6 8 1 5 . 0 0 9 . 5 2 ( 0 . 4 8 ) ( 0 . 2 0 ) ( 0 . 3 3 ) ( 3 . 7 0 ) ( 3 . 3 4 ) ( 8 . 3 6 ) ( 1 1 . 7 9 ) ( 0 . 4 0 ) ( 0 . 2 8 ) ( 0 . 3 7 ) ( 0 . 6 0 ) ( 0 . 3 5 ) ( 0 . 2 3 ) ( 0 . 4 4 ) ( 0 . 3 1 ) 1 2 . 0 1 4 . 9 1 8 . 0 2 3 4 . 0 2 3 1 . 5 2 9 2 . 4 8 1 5 9 . 3 0 8 . 4 8 6 . 9 7 1 2 . 8 4 2 6 . 7 9 9 . 3 1 5 . 3 6 1 3 . 8 3 9 . 2 3 ( 0 . 7 3 ) ( 0 . 3 7 ) ( 0 . 4 4 ) ( 7 . 0 9 ) ( 5 . 3 0 ) ( 1 5 . 6 7 ) ( 3 3 . 6 3 ) ( 0 . 5 4 ) ( 0 . 5 0 ) ( 0 . 4 6 ) ( 0 . 9 0 ) ( 0 . 5 0 ) ( 0 . 3 2 ) ( 0 . 5 2 ) ( 0 . 6 3 ) 1 2 . 1 4 4 . 9 0 7 . 9 7 3 9 . 3 2 3 3 . 2 6 9 3 . 3 7 1 6 7 . 7 9 8 . 6 1 6 . 7 8 1 2 . 3 3 2 6 . 8 7 9 . 8 3 5 . 0 9 1 3 . 9 8 9 . 3 5 ( 0 . 7 4 ) ( 0 . 2 2 ) ( 0 . 2 6 ) ( 4 . 7 2 ) ( 4 . 3 0 ) ( 7 . 3 2 ) ( 1 3 . 3 3 ) ( 0 . 3 0 ) ( 0 . 2 7 ) ( 0 . 3 9 ) ( 0 . 3 9 ) ( 0 . 3 2 ) ( 0 . 2 5 ) ( 0 . 3 8 ) ( 0 . 3 1 ) 1 2 . 5 6 5 . 1 7 7 . 9 3 3 4 . 5 2 3 3 . 4 9 9 2 . 4 2 1 6 0 . 7 1 9 . 0 1 7 . 2 3 1 2 . 9 8 2 6 . 9 4 9 . 4 6 5 . 2 9 1 4 . 3 0 9 . 12 ( 0 . 4 5 ) ( 0 . 2 0 ) ( 0 . 3 8 ) ( 6 . 2 2 ) ( 5 . 1 0 ) ( 1 0 . 0 6 ) ( 1 5 . 9 7 ) ( 0 . 4 3 ) ( 0 . 2 8 ) ( 0 . 3 5 ) ( 1 . 1 4 ) ( 0 . 3 2 ) ( 0 . 1 8 ) ( 0 . 3 5 ) ( 0 . 2 6 ) 12 .60 5 . 1 6 7 . 9 3 3 9 . 6 4 3 2 . 6 4 68.13 1 5 9 . 7 4 9 . 1 4 7.19 13.31 2 6 . 5 6 9 . 5 8 5 . 2 2 1 4 . 5 5 9 . 4 7 ( 0 . 5 2 ) ( 0 . 2 3 ) ( 0 . 5 0 ) ( 5 . 9 1 ) ( 4 . 7 3 ) ( 1 1 . 9 5 ) (19.39) ( 0 . 4 8 ) ( 0 . 3 5 ) ( 0 . 5 1 ) ( 0 . 7 8 ) ( 0 . 4 2 ) ( 0 . 2 2 ) ( 0 . 3 2 ) ( 0 . 5 0 ) 12.18 5 . 0 1 8 . 4 6 3 8 . 7 1 3 7 . 0 1 9 5 . 0 9 1 7 0 . 8 9 6 . 8 0 6 . 9 1 1 2 . B l 2 7 . 0 9 9 . 6 0 5 . 2 0 1 3 . 9 5 9 . 3 4 ( 0 . 5 4 ) ( 0 . 4 4 ) 1 0 . ( 1 I ( 6 . 6 3 ) ( 5 . 1 2 ) ( 9 . 8 6 ) (16.16) (0.66) ( 0 . 4 3 ) ( 0 . 6 5 ) ( 1 . 3 2 ) ( 0 . 4 7 ) ( 0 . 2 6 ) 1 0 . 5 3 ) ( 0 . 5 6 1 12.18 5 . 0 1 8 . 0 1 4 0 . 0 9 3 6 . 6 0 1 0 2 . 4 0 1 7 9 . 3 5 8 . 6 6 6 . 7 4 1 2 . 4 0 2 6 . 5 0 9 . 6 8 5 . 0 5 1 4 . 2 1 9 . 2 6 ( 0 . 5 C ) ( 0 . 3 0 ) ( 0 . 3 6 ) ( 3 . 8 3 1 (4.12) (12.45) (18.65) 1 0 . 3 8 ) ( 0 . 3 7 ) ( 0 . 3 3 ) ( 0 . 5 0 ) ( 0 . 4 4 ) ( 0 . 2 7 ) ( 0 . 4 4 ) ( 0 . 2 5 ) 8 . 7 1 7 . 1 4 7 . 0 2 J 2 . 7 0 5 0 . 2 8 4 3 . 7 8 5 9 . 1 1 8 . 7 9 6 . 0 7 1 5 . 3 2 3 . 3 2 13 . 62 1 3 . 2 2 4 3 . 0 8 6 . 4 9 0 . 0 0 0 1 0 . 0 0 0 1 0 . 0 0 0 1 0 . 0 0 0 1 0 . 0 0 0 1 0 . 0 0 0 1 0 . 0 0 0 1 0 . 0 0 0 1 0 . 0 0 0 1 0 . 0 0 0 1 0 . 0 0 0 9 0 . 0 0 0 1 0 . 0 0 0 1 0 . 0 0 0 1 0 . 0 0 0 1 7 8 8 2 ) 2 7 2 3 2 5 6 8 16 I 15 14 2 2 5 "3 T a b l e A.2 F - m a t r i x f r o m MANOVA f o r d i f f e r e n c e s between p o p u l a t i o n c e n t r o i d s among 10 p o p u l a t i o n s o f j u v e n i l e coho salmon (see e q u a t i o n s 5-7). A l s o i n d i c a t e d a r e Mean F v a l u e s f o r i n t e r i o r - i n t e r i o r ( I - I ) , c o a s t a l - c o a s t a l (C-C) and c o a s t a l - i n t e r i o r ( C - I ) p a i r w i s e c o m p a r i s o n s . F-MATRIX DEGREES OF FREEDOM ARE 12 370 LEM EBAR CW LOU SILV WADE DEM KIRB MORR EBAR 16.23 CW 26.07 28.05 LOU 25.79 17.21 33 .50 SILV 28.52 36.94 24 .64 27 .24 WADE 42.60 39.58 8 .02 39 .72 17. 12 DEM 24.24 27.82 31 .69 26 .76 7. 97 30.76 KIRB 22.99 24.54 33 .79 24 .55 15. 57 31 .81 7.25 MORR 50.54 36.13 14 .48 34 .45 20. 61 4.07 31.33 32. 03 ROSE 41 .04 44.90 22 .64 32 .69 7. 51 11.21 15.65 20. 91 Mean I-I = 24.48, Mean C-C «= 17.61, Mean C-I - 30.85 i l T T a b l e A.3 A d j u s t e d g e o m e t r i c means ( +. SD, mm) and r e s u l t s o f ANOVA f o r C o l d w a t e r R i v e r , M o r r i s o n C r e e k and Wade C r e e k w i l d coho sa l m o n , 1982. O v e r a l l mean s t a n d a r d l e n g t h i s 64 mm. F i n a r e a s a r e i n s q . mm. Character Coldwater R. Morrison Cr. Wade Cr. F{2,117) P Bodyd 14.06 (0.59) 14.11 (1.29) 15.94 (0.83) 50.95 < 0.0001 Pedd 5.85 (0.26) 6.25 (0.27) 6.28 (0.29) 30.88 < 0.0001 Pedl 10.70 (0.41) 10.25 (0.53) 10.77 (0.48) 13.78 < 0.0001 DFA 52.69 (4.70) 52.79 (5.32) 47.35 (6.42) 12.66 < 0.0001 AFA 43.87 (4.71) 42.40 (4.57) 40.66 (3.74) 5.44 < 0.006 CFA 152.24 (13.37) 143.51 (13.88) 146.70 (11.69) 4.62 < 0.05 TMFA 248.54 (17.93) 238.61 (20.86) 235.05 (18.0l) 5.42 < 0.006 Pecf 11.57 (0.50) 10.95 (0.52) 11.87 (0.50) 33.86 < 0.0001 Pelvf 9.31 (0.36) 8.44 (0.38) 9.35 (0.38) 74.71 < 0.0001 SNAP 17.27 (0.56) 16.17 (0.50) 16.99 (0.56) 44.78 < 0.0001 SNAPE 35.80 (1 .18) 33.91 (1.15) 35.23 (0.73) 34.80 < 0.0001 BWBD 11.09 (0.44) 11.66 (0.75) 12.44 (0.56) 51.58 < 0.0001 FR 5.77 (0.23) 5.51 (0.38) 5.14 (0.23) 48.17 < 0.0001 HL 18.86 (0.55) 17.86 (0.61) 19.02 (0.56) 47.90 < 0.0001 HD 11.84 (0.3B) 12.08 (0.48) 12.53 (0.42) 26.31 < 0.0001 T a b l e A.4 A d j u s t e d g e o m e t r i c means ( +. SD, mm) and r e s u l t s o f ANOVA f o r C o l d w a t e r R i v e r , M o r r i s o n C r e e k and Wade C r e e k w i l d j u v e n i l e c o ho salmon, 1983. O v e r a l l mean s t a n d a r d l e n g t h i s 52 mm. F i n a r e a s a r e i n s q mm. Character Coldwater R. Morrison Cr. Wade Cr. F{2,117) P Bodyd 12.94 (0.60) Pedd 5.13 (0.22) Pedl 6.55 (0.28) DFA 36.10 (5.08) AFA 30.68 (3.26) CFA 91.63 (5.74) TMFA 158.89 (13.14) Pecf 9.17 (0.36) Pel v f 7.24 (0.25) SNAP 13.45 (0.77) SNAPE 28.87 (1.05) BWBD 10.41 (0.51) FR _ 5.15 (0 . 19 ) HL 15.58 (0.43) HD 10.10 (0.29) 13.07 (0.57) 13.16 5.32 (0.31) 5.19 6.64 (0.39) 8.59 44.43 (5.33) 45.77 36.75 (4.76) 39.41 103.84 (8.15) 115.20 184.48 (14.65) 200.47 9.43 (0.42) 9.09 7.38 (0.41) 7.10 13.44 (0.36) 13.01 28.9? (0.55) 29.01 10.50 (0.48) 10.78 5.10 (0.23) 4.97 15.20 (0.47) 14.80 9.97 (0.26) 10.03 (0.80) 1. 94 > 0. 1 (0.23) 5. 49 < 0. 006 (0.28) 0. 85 > 0. 1 (4.42) 27. 73 < 0. 0001 (4.44) 45. 44 < 0. 0001 (9.43) 69. 64 < 0. 0001 (14.58) 88. 78 < 0. 0001 (0.32) 9. 49 < 0. 0002 (0.29) 7. 38 < 0. 001 (0.41) 8. 6B < 0. 0004 (0.42) 0. 46 > 0. 1 (0.55) 5. 47 < 0. 006 (0.25) 5. 36 < 0. 006 (0.41) 31. 34 < 0. 0001 (0.33) 2. 21 > 0. 1 115* T a b l e A.5 A d j u s t e d g e o m e t r i c means ( +. SD, mm) and r e s u l t s of ANOVA f o r C o l d w a t e r R i v e r , M o r r i s o n C r e e k and Wade C r e e k l a b o r a t o r y r e a r e d j u v e n i l e c o h o . O v e r a l l mean s t a n d a r d l e n g t h i s 52 mm. F i n a r e a s a r e i n s q . mm. Character Coldwater R. Morrison Cr. Wade Cr. F{2,117} P Bodyd 11 .74 (0.38) 12.57 (0.53) 13.25 (0.63) 83.57 < 0. 0001 Pedd 4.86 (0 .18 ) 5.03 (0.21) 5.26 (0.19) 43.85 < 0. 0001 Pedl B.40 (0.28) 8.45 (0.24) 8.10 (0.31) 18.58 < 0. 0001 DFA 33.93 (3.45) 38.53 (3.84) 43.11 (4.92) 49.57 < 0. 0001 AFA 30.32 (2.73) 33.61 (3.58) 34.94 (4.02) 17.55 < 0. 0001 CFA 93.99 (5.77) 96.85 (5.80) 96.66 (7.29) 6.03 < 0. 004 TMFA 157.57 (9.88) 169.56 (10.34) 177.21 (13 .18) 31.15 < 0. 0001 Pecf 8.70 (0.34) 8.77 (0.38) 8.99 (0.33) 7.46 < 0. 0009 Pelvf 7.05 (0.26) 7.22 (0.29) 7.23 (0.22) 5.69 < 0. 005 SNAP 12.93 (0.31) 12.93 (0.30) 12.74 (0.35) 4.76 < 0. 05 SNAPE 28.15 (0.49) 28.42 (0.43) 28.37 (0.61) 3.14 < 0. 05 BWBD 9.70 (0.36) 10.20 (0.33) 10.84 (0.61 ) 65.73 < 0. 0001 FR 5.37 (0.20) 5.09 (0.18) 4.80 (0.27) 69.69 < 0. 0001 HL 14.36 (0.78) 14.54 (0.31) 14.64 (0.35) 2.74 > 0. 05 HD 9.71 (0.25) 9.70 (0.25) 9.97 (0.29) 13.70 < 0. 0001 T a b l e A.6 R e l a t i v e c h a r a c t e r r a n k s f o r j u v e n i l e c o ho salmon from C o l d w a t e r R i v e r ( C W ) , M o r r i s o n C r e e k (MC) and Wade C r e e k (WC),1982,1983 w i l d and 1982/83 l a b o r a t o r y r a i s e d s a m p l e s . Ranks i n d i c a t e d e c e n d i n g o r d e r o f r e l a t i v e m a g n i t u d e . Character Wild 1982 Wild 1983 Laboratory CW MC WC CW MC WC CW MC WC Bodyd 2 2 1 3 2 1 3 2 1 Pedd 3 2 1 3 1 2 3 2 1 Pedl 2 3 1 3 2 1 2 1 3 DFA 1 2 3 3 2 1 3 2 1 AFA 1 3 2 3 2 1 3 2 1 CFA 1 2 3 3 2 1 3 2 1 TMFA 1 2 3 3 2 1 3 2 1 Pecf >' 2 3 1 2 1 3 3 2 1 Pelv f 2 3 1 2 1 3 3 2 1 SNAP 1 3 1 2 3 • 1 1 3 SNAPE 3 2 1 3 2 1 3 1 2 BWBD 3 2 1 3 2 1 3 2 1 FR 1 2 1 2 3 1 2 3 HL 2 3 1 1 2 3 3 2 1 HD 3 2 1 1 3 2 2 3 1 

Cite

Citation Scheme:

        

Citations by CSL (citeproc-js)

Usage Statistics

Share

Embed

Customize your widget with the following options, then copy and paste the code below into the HTML of your page to embed this item in your website.
                        
                            <div id="ubcOpenCollectionsWidgetDisplay">
                            <script id="ubcOpenCollectionsWidget"
                            src="{[{embed.src}]}"
                            data-item="{[{embed.item}]}"
                            data-collection="{[{embed.collection}]}"
                            data-metadata="{[{embed.showMetadata}]}"
                            data-width="{[{embed.width}]}"
                            async >
                            </script>
                            </div>
                        
                    
IIIF logo Our image viewer uses the IIIF 2.0 standard. To load this item in other compatible viewers, use this url:
http://iiif.library.ubc.ca/presentation/dsp.831.1-0096165/manifest

Comment

Related Items